Category: GQT: your gardening queries answered


Now is the perfect time to plant trees and shrubs. Recently, I’ve had a question from Charles Windsor, who lives near London:

“We have a small garden with little space, but would like a tree

to emphasise the vertical dimension. What would you suggest?”

It’s amazing what putting strong verticals into small spaces does- somehow it defines the space and it looks bigger! Trees that have a narrow profile- otherwise known as fastigiate– would be best in your garden, Charles. Some possibilites include:

  • Prunus serrula ‘Amanogawa’– a flowering cherry with double pink flowers and good autumn colour

  • the ‘Maidenhair Tree’ (Ginkgo biloba), in its fastigiate form, the leaves of which are larger versions of those of the maidenhair fern and which turn yellow in autumn

  • Chamaecyparis lawsoniana ‘Alumii’– a blue-grey form of of the Lawson Cypress

  • Taxus baccata ‘Fastigiata’– a narrowly growing Yew

If you have a garden which is a little bigger (it can take trees with a wider spread), for trees with good all year round interest, try:

  • Arbutus unedo– the ‘Strawberry Tree’- shining evergreen folioage, clusters of white flowers in autumn and early winter, and red fruits which change colour slowly through the year until they mature the following autumn. It grows to around 4 metres tall and needs a mild climate, though it can withstand gales.

  • Ornamental Crab apples (Malus) grow to between 3.5m and 6m tall, are hardy, easy to grow and attractive for most of the year, with crimson, red, pink or white spring flowers, yellow or red fruit and good autumn colour, wiht purple leave sin sowem varieties.

  • Amelanchier lamarckii (‘Snowy Mespilus’)– white spring flowers followed by black berries and wonderful autumn leaf colour, this and other species/cultivars (we have Amelanchier canadensis here at Old School Garden) grow to a mature height of between 6 and 10 metres.

Further information:

Trees for smaller gardens- RHS

10 Best trees for smaller gardens- The Guardian

Trees for Small Gardens- Gardeners’ World

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and join others by signing up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

Advertisement

I recently had a ‘tweet’ from fellow Norfolk resident, Claire in Thetford. She was wondering what the growths on these leaves were.

I must admit to being a bit puzzled at first, but some further research suggested that they are some sort of Gall, which Wikipedia describes as:

‘…abnormal outgrowths of plant tissues and can be caused by various parasites, from fungi and bacteria, to insects and mites. Plant galls are often highly organized structures and because of this the cause of the gall can often be determined without the actual agent being identified. This applies particularly to some insect and mite plant galls.’

My guess from the pictures was that these were galls possibly created by some sort of parasitic wasp (in this case on the leaves of a Lime Tree). Claire’s own research came up with a more precise description: a ‘Nail Gall’ formed by a small mite Eriophyes tiliae. These microscopic mites overwinter in the bark of lime trees and crawl on to the underside of the foliage in spring to feed. The mites secrete chemicals into the leaves causing them to produce the unusual projections into which the mites move to continue feeding during the summer. Infestations of mites and the nail galls they induce don’t appear to affect the health of the trees and there’s no way of controlling or preventing them. The galls caused by this mite are said to be yellow-green or red in colour (see picture below). It may be that the whitish nails in Claire’s picture have been be caused by another mite (Aceria lateannulatus), which affects both the small-leaved lime (Tilia cordata) and the Common Lime (Tilia x europaeus), but not the large-leaved lime (Tilia platyphyllos).

Nail Galls cauised by Eriophyes tiliae

Nail Galls cauised by Eriophyes tiliae

Galls are fascinating phenomena. As Wikipedia continues, those created by insects are:

‘…highly distinctive plant structures formed by some herbivorous insects as their own microhabitats. They are plant tissue which is controlled by the insect. Galls act as both the habitat and food source for the maker of the gall. The interior of a gall can contain edible nutritious starch and other tissues. Some galls act as “physiologic sinks”, concentrating resources in the gall from the surrounding plant parts. Galls may also provide the insect with physical protection from predators.

Insect galls are usually induced by chemicals injected by the larvae or the adults of the insects into the plants, and possibly mechanical damage. After the galls are formed, the larvae develop inside until fully grown, when they leave. In order to form galls, the insects must seize the time when plant cell division occurs quickly: the growing season, usually spring in temperate climates, but which is extended in the tropics.

The meristems, where plant cell division occurs, are the usual sites of galls, though insect galls can be found on other parts of the plant, such as the leaves, stalks,branches, buds, roots and even flowers and fruits. Gall-inducing insects are usually species-specific and sometimes tissue-specific on the plants they gall.’

Galls are also caused by fungi, bacteria, viruses and nematodes. It seems that in many instances these growths do not cause any significant harm to the plants they infest, though in some cases long term harm can be caused to some species, for example by affecting their overall shape and vigour.

Crown Gall on apple- RHS

Crown Gall on apple- RHS

Crown gall affects a wide array of plants and roses are definitely one of them. It is a plant disorder caused by the bacterium Agrobacterium tumefaciens, that interferes with the plants ability to take up water and nutrients. This results in poor growth and weak plants that are easily stressed and injured- the only remedy in this case is to dig up the plant and dispose of it.

The study of plant galls is called cecidology. While these weird structures have intrigued humans for many years, there is still much that we don’t know about them.

Wiches Broom Gall - picture Rosser1954

Wiches Broom Gall – picture Rosser1954

While some galls are well hidden and hard to spot, others are much more conspicuous. Have you ever looked up into a birch tree (Betula spp.) and noticed what looked like large, dense birds’ nests? In some cases these may well be nests, but very often they are actually galls called ‘witches’ brooms’. These are caused by a fungus (Taphrina betulina), which stimulates the tree to produce numerous extra shoots, resulting in a dense nest-like cluster. The fungus can then feed on the shoots. It was once believed that they were caused by witches flying over the tree!

If you spot an odd-looking growth on a dog rose (Rosa canina) it could well be a Robin’s pincushion gall, caused by a wasp (Diplolepis rosae). There was once a belief in England that these were caused by the woodland sprite, Robin Goodfellow or Puck. It is hardly surprising that people ascribed supernatural causes to some galls – they look pretty strange, and their causes aren’t exactly obvious.

'Robins Pincushion' gall on a Wild rose

‘Robins Pincushion’ gall on a Wild rose

The real gall specialists include gall midges, gall flies and gall wasps. Perhaps one of the most familiar galls is the oak apple, caused by a tiny wasp (Biorhiza pallida).

Oak apples

Oak apples

There are actually hundreds of species of oak gall wasps and they cause a fantastic variety of galls on oaks (Quercus spp.). A single oak tree may support many thousands of galls. Each gall wasp species creates its own unique and outlandish structure: some resemble cotton wool or marbles, pineapples or tiny UFOs!

Here’s a gallery of some of the other amazing galls to be found.

This slideshow requires JavaScript.

Sources and further information:

Galls- Wikipedia

Eriphyes tiliae- Wikipedia

British Plant Gall Society

Trees for Life- Galls

RHS- Crown Gall

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and join others by signing up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

Flower of the yellow Tree Peony - can be a long time coming, but worth the wait!

Flower of the yellow Tree Peony – can be a long time coming, but worth the wait!

Nick (from Cheshire), and an old friend of mine, contacted me recently with a sad tale:

‘Found my lovely tree peony snapped off at the base. It had taken about 3 or 4 years to flower and this year produced a massive single bloom, so I was hoping for more next year. We think the window cleaner might be to blame. I’ve planted up a few cuttings and it had produced 4 massive seed pods. Do you think there’s any chance of rearing the cuttings or germinating the seeds?’

Oh dear, I know how long it can take to get a flowering tree peony, having had one (Paeonia delavayi f. lutea), for at least 10 years, and only now getting some blooms. I think you’ve got three approaches to try and resurrect this wonderful deciduous shrub, Nick, but all will probably take a further few years to result in any notable blooms, I’m afraid:

1. You might be lucky and get some re-growth from the base of the plant, so don’t dig it up. Check if the break occurred above or below any graft point(most commercially grown Tree Peonies are grown on the roots of their more vibrant herbaceous cousins). If it’s above, you’ll possibly get another tree peony growing, if below it might turn into an herbaceous variety! You might give it a feed of Blood, Fish and Bone or another ‘balanced’ fertiliser to give it a kick-start (or rather re start) in the current growing season.

2. Your taking of cuttings is a good policy, but again these will be slow to produce much growth, let alone flowers. Hopefully you’ve taken ‘semi ripe’ cuttings of fresh growth, and planted these in the usual way, but I’m afraid the ‘strike rate’ may be low. Another form of vegetative propagation for Tree Peonies is layering but this requires a healthy shoot attached to the plant, an option you probably don’t have, and one which has mixed success too!

3. Yes, it’s worth having a go with seed. Make sure it’s ripe before you sow it (put the seed heads in a paper bag and wait for the seeds to dry a bit and fall out of the head naturally). Then sow these around now (late summer, early autumn) about 1″ deep in a soil-based seed compost, cover lightly with grit and put the pots outside. Make sure that the compost does not dry out and protect the pots from rodents. Tree peony seeds require two periods of cold – known as  ‘double dormancy’- with a warm period in between. After the first cold period the roots will develop, but you’ll see little if any top growth. The second season you should see some top growth and you can pot up the seedlings as they outgrow their pots- unfortunately it will probably be 5 years before they are of flowering size!

The RHS say about flowering problems with established Tree Peonies:

‘Tree peonies can take up to four years to settle in and flower, even though the plant may have been bought in bloom.

However, the lack of flowers can be also caused by shallow planting. If the plant did not produce flowers for several years after planting, try lifting it in the autumn and replanting it deeper.

Though established plants are drought tolerant, prolonged periods of drought may affect the flowering the following season. Mulch around the base and water during prolonged periods of dry weather.

Tree peonies planted in shady position tend to flower less profusely. Cut overhanging branches to allow more light to reach the plant. If this is not possible consider moving it.’

I wonder if you can get some free window cleaning on the back of this accident, Nick?!

Further information:

RHS- Tree Peonies

Plantax 9: Paeonia – physician of the gods

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and join others by signing up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

The English Walnut- creating a planting poser...

The English Walnut- creating a planting poser…

Whilst on holiday in Suffolk, recently, one of my friends, Richard (who lives in Bristol), posed an interesting question:

‘I have a Walnut Tree in the garden and have been trying to grow some plants in a raised area underneath it, against a wall. This area only gets early morning sun during the middle of the year. I believe that Walnuts deposit some sort of poison in the ground which affects the plants? Over 20 years I’ve managed to establish a small selection of plants through trial and error (mainly the latter); geraniums give some cover and with a ‘Chelsea Chop’ may give a second flowering, but only towards the lighter edge of the bed; Ivy seems to do well; I can squeeze out some summer colour by planting some annual begonias but these need a lot of watering. I’ve also tried several different ferns, but none have been a success to date. Any thoughts about planting the area, especially towards the back, would be welcome.’

Not having come across this issue before I did a bit of research and also sought some advice from the RHS Member’s Advice Service. There are two main species of Walnut tree; Black Walnut (Juglans nigra) – most common in North America (and native to eastern areas), and the English Walnut (Juglans regia), the type most often found in the U.K. Walnuts -especially Juglans nigra– contain a chemical called “juglone” which can be poisonous (or allelopathic) to other plants. Juglone appears to act as a respiration inhibitor which deprives sensitive plants of needed energy for metabolic activity.  For gardeners this means that many plants growing in the vicinity of a black walnut tree will either be killed or will struggle to live, with yellowing, wilting leaves.

Leaves and nuts on the Black Walnut

Leaves and nuts on the Black Walnut

Juglone is found in all parts of the black walnut tree, but it is most concentrated in the flower buds, nut hulls and roots. Unfortunately the roots of a black walnut can extend 3-4 times the diameter of the tree’s canopy, so the area affected is quite wide. Toxicity is further dependent on the soil’s texture and drainage. All walnuts – including the English Walnut- produce some juglone, as do the walnut relatives bitternut hickory, hickory, pecan and shagbark. However the amount of juglone produced is insignificant, compared to the black walnut, and the effect on other plants is minimal, if any.

Tomatoes seem to be the most sensitive to growing under black walnuts. However juglone sensitivity is also dependent on other growing conditions and what will or won’t grow under one black walnut tree may be fine under another. However, here is a compiled list of flowers and vegetables that are considered extremely sensitive to juglone.

Turning back to Richard’s question, Guy Barter, Chief Horticultural Adviser at the RHS, says:

‘In theory English walnuts secret Juglone and we would advise that it is not underplanted – in any case they cast such a heavy shade that few plants will thrive underneath a walnut. Of course roots spread out beyond the canopy but interestingly we seldom encounter difficulties in the UK. All the same it may be well to avoid apples and tomatoes near a walnut tree, or at least make some experimental plantings in the first instance. In the USA the light levels are very much higher and underplanting options greater and it is not surprising that problems arise.’

Not very encouraging, eh, Richard? You seem to have had some success with plants nearer the lighter edge of his planting area, and if you want to persist with trying to plant up this and the darker inner area, you might want to start by improving the growing conditions; maybe you can prune the tree a little to raise the crown and let in more light? Having a raised bed underneath is good because you can deepen the soil above the tree roots; and maybe you can also try to replace the topsoil which could over time become affected by juglone? It might also be a good idea to add organic matter each year and at the same time remove all the walnut tree leaves and litter and dispose of these – it’s probably best to avoid composting it.

As to planting, for the inner area (assuming that you can find planting pockets large enough around any tree roots), I’d try out a few small to medium – sized shrubs and other plants that tolerate heavy shade and dryish soil – in effect trying to create an ‘understorey’ with plants of varying heights and in a combination to provide something of interest all-year round. If you go down this route then try to get healthy, well-established plants (2-3 years old and/or in 3 litre pots). As Guy suggests, you’ll have to ‘trial’ these to see if they’re up to the task! My recommended ‘planting scheme’ would include, for the darkest area (and maybe including some Ivy as ground cover):

  • Lonicera pileata– spreading evergreen shrub with small creamy flowers in spring followed by purple berries; height 60cm (2ft), spread 2.5m (8ft)
  • Hypericum calycinum (‘Rose of Sharon’) – spreading shrubs with yellow flowers from mid summer. Height 60cm (2ft), spread indefinite
  • Vinca minor (lesser periwinkle) – mat-forming shrub with trailing shoots and violet-blue flowers from mid-spring to autumn. Height 10-20cm (4-8in), spread indefinite
Lonicera pileata

Lonicera pileata

If you’d like to increase the variety of your planting around the edge (and lighter) area, you could try in addition to your geraniums:

  • Cotoneatser simonsii– deciduous or semi-evergreen with good autumn leaf colour; small pink flowers in summer followed by bright orange-red fruit. Height 2.5m (8ft), spread 2m (6½ft)
  • Mahonia aquifolium– evergreen with yellow blooms in spring. Height 90cm (3ft); spread indefinite.
  • Sarcococca hookeriana var. humilis (Christmas box)- evergreen with scented flowers in winter. Height 60cm (2ft); spread 1.2m (4ft)

…and a couple of herbaceous perennials:

  • Bergenia– evergreen leaves may colour in winter; white, pink or red flowers in spring. Height 20-45cm (8-18in), spread 45-63cm (18-25in)
  • Tellima grandiflora – semi-evergreen, with greenish white flowers from spring to mid-summer. Self-seeds freely. Height 40cm (16in), spread 25cm (10in)

Tellima grandiflora

Tellima grandiflora

…and maybe one or two patches of bulbs/tubers?

  • Anemone nemorosa– white flowers from spring to early summer. Height 7.5-15cm (3-6in), spread more than 30cm (1ft)
  • Cyclamen hederifolium– attractively marked foliage and pink to maroon flowers in autumn, seeds freely. Height 10-13cm (4-5in), spread 15cm (6in)
  • Galanthus nivalis (snowdrop) – white flowers in late winter. Height and spread 10cm (4in)
  • Iris foetidissima (stinking iris) – blue flowers in late spring and orange berries in autumn/winter. Height and spread 40cm (16in)

If this all seems rather too much hassle, then you could always cover the bed with a landscape fabric and then put a layer of aggregate or other mulch- wood bark, slate chippings etc. This covering could be punctured at intervals for clumps of bulbs (see above) to give you some (simpler) interest throughout the year- and maybe end the years of heart ache trying to get things to work that just don’t stand much of a chance!

Sources and further information:

Black walnuts at About.com

RHS guide to planting under trees

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and join others by signing up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

The Lime Walk at Arley Hall, Cheshire, an example of pleaching
The Lime Walk at Arley Hall, Cheshire, an example of pleaching

It’s that time of year when the summer growth of hedges – at least those that need to be kept in trim- is being cut back. Joe Sloley from Hintlesham has an interesting opportunity with one of his hedges:

‘I have a row of overgrown lime trees which originally formed a screen and which I want to cut back and pleach. Are limes suitable for this kind of training and what are the details of the method?’

Pleaching or plashing (an early synonym) was common in gardens from late medieval times to the early eighteenth century. It means the interweaving of growing branches of trees and shrubs to form a hedge, living fence or arbour which provides a strong barrier, shaded paths or garden features.  The word ‘plexus’ derives from the same Latin root word ‘plecto’, meaning to weave or twist together. This craft had originally been developed by European farmers who used it to make their hedgerows more secure.

 "Walking in a thick pleached alley in mine orchard" - William Shakespeare, 'Much Ado About Nothing'

Pleached Trees and an underlying Yew hedge ay Dipley Mill, Hampshire, via  Angus Kirk

Pleached Trees and an underlying Yew hedge ay Dipley Mill, Hampshire, via
Angus Kirk

Today the term tends to be used to refer to what might be called the process of creating a ‘hedge on stilts’ where (usually smooth-barked) trees have their lower side growth removed and the higher growth is pruned and trained to form a continuous, elevated hedge.

Limes can certainly be pleached: they have pliable growth, and the shoots rapidly grow long enough to be woven in and out. Once the trees have been cut back to the height you require, the lower part of the trunks should be cleared of side growths. Then attach horizontal canes or wires to the trunks and across the gaps between the trees. Allow new shoots to grow out sideways; any which grow forwards or backwards should be pruned out completely. The side shoots are tied to the canes/ wires and when plentiful enough are interwoven with one another. As the shoots mature into branches, the canes or wires can be dispensed with and new growth trained amongst the old.

Pleaching in process

Pleaching in process

Tilia (lime) is the most commonly used tree for pleached walks; usually the red-twigged lime (Tilia platyphyllos ‘Rubra’).  Ash, beech, chestnut, hornbeam and plane can also be pleached, as can apples and pears. These can often be obtained ready trained.

Laburnum and Wisteria are favoured for pleached arbours and covered walks, especially tunnels, which show off the attractive flowers perfectly.  Use Wisteria grown from cuttings or raised by grafting, as it will flower more reliably and uniformly than seed-raised plants, and Laburnum x watereri ‘Vossii’ is a better choice than seed-raised L. anagyroides.

If you want to start a pleached hedge, select young, whippy plants that are more easily trained. Plant these out in winter and during the early years also prune in the winter when the plants are leafless and dormant. Train and tie new shoots in over the summer. Once pleached trees have reached their full extent, prune in the summer, pruning to shape the new growth and reduce the tree’s vigour.

Here’s a fascinating example of how pleaching could be used to ‘grow homes’!

fab-tree-hab

Further information:

Wikipedia

RHS guide to pleaching

Pleaching- the art of taming nature by Jardin Design

See through boundaries

Healthy Hedges with Crisp Edges

Old School Gardener

raspberriesSummer fruiting raspberries are just about coming to the end here at Old School Garden, but Lee Mason of Whetstone has had a disappointing harvest:

‘I planted some ‘Malling Promise’ raspberry canes back in February. They’ve grown pretty well, but the harvest has been disappointing and the new growth looks to be weak. Would a fertiliser feed help?’

Malling Promise canes (and any other summer fruiting raspberries for that matter), planted in February would have benefitted from cutting down in their first season to 100 mm (4 inches) high canes back in March to encourage strong new root development, as well as new canes for fruiting in the following season. In short, Lee, you’ve ‘got a bit ahead of yourself’!  I suggest that you cut down all growth next March. You will lose a season’s cropping, but the sacrifice will be worth it in the long run. Giving the canes a good mulch of organic matter or a general fertiliser like fish, blood and bone should also help, if applied next spring.

Raspberry flavour

Have you been disappointed with the flavour of your raspberries? Sulphate of potash is a good fertiliser to use  to enhance raspberry flavour, but only if the raspberry variety you grow has some natural flavour of it’s own. Varieties like Malling Admiral have little natural flavour, whereas Malling Jewel or Malling Promise are better.

Shrivelled fruit

Are your raspberries shrivelled up? This might be because you’ve been a little too enthusiastic in digging around the canes! Avoid digging over the ground near the roots, as raspberries are surface rooters and don’t like any cultivation anywhere near the canes. This breaks the roots- which can spread out quite a way- and as a result the plants will be unable to cope with the extra stress at fruiting time. If you restrict your cultivation to the use of a Dutch hoe and follow this up with a good deep mulch of organic matter in the spring this will do wonders for the quality of your fruit.

Cut down the canes of autumn fruiting raspberries in early March
Cut down the canes of autumn fruiting raspberries in early March

Pruning Autumn (and Summer) raspberries

The first autumn raspberries are starting to appear here at Old School Garden (earlier than normal probably due to the mild winter and spring). It looks like we’ll have a good harvest. With these, the fruit comes on canes produced in the current season, so after fruiting (which can last into October) the old canes need to be cut back, but when is the best time to do this? Well not immediately after harvesting, apart from damaged or broken canes. It’s best to leave the rest until the following spring (early March), when all the remaining canes can be cut down almost to ground level. This ensures that some protection for the newly emerging canes is provided over winter. In July weak growth can be removed so that only the strongest canes are left for fruiting.

With summer fruiting varieties it’s best to cut down the canes that have fruited immediately after harvesting has finished and to select the strongest new canes and tie these into wire supports to protect them over winter. In spring the tops can be cut back by about 6 inches or alternatively these can be looped over and tied into the top wires.

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and join others by signing up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

shady greenhouseI’ve previously had a question about acquiring a second greenhouse and what it could be used for. Today’s question is from Tony Sharp of Hertford and also involves a ‘greenhouse gift’. Tony asks:

‘My parents have offered me their old greenhouse, but the only available space for it in my garden is generally shaded. Is it worth the trouble of moving it to my place?’

Tony, it is certainly worth it. The great majority of popular greenhouse and pot plants prefer shady conditions when in the decorative stage- but good light, which does not mean direct sunlight under glass, is essential for them in their early stages of growth. If there is too much gloom, growth will be weak, straggly and pale. If your greenhouse is going to be very shaded, the use of a cold frame or other mini garden frame in a more open, sunny position might provide the right light levels for the early growth stages of some plants.

There are also many plants that revel in considerable shade, apart from the low growers suitable for placing under the staging (more on this below). Examples include:

  • Many ferns for both cool and warm conditions

  • Norfolk island pine (Araucaria excelsa) in its juvenile form

  • The climbers, Chilean bell-flower (Lapageria rosea) and Hoya carnosa- both with attractive flowers

  • Many ivies

  • The Schefflera foliage species

  • Camellias, which flower very well in pots when young

  • Streptocarpus

  • Gloxinias

  • Many of the Gesneria family

  • The ‘forest cacti’ such as Schlumbergera and Rhipsalidopsis

  • The annual Exacum affine, which is sweet-smelling

  • Anthurium crystallinum

  • Various palms

And there are many more possibilities to choose from depending on the temperature that can be maintained in the greenhouse.

I mentioned using the space under the staging in the greenhouse above. If you have a glass-to ground greenhouse the lighting conditions will probably allow this area to be used for a propagator or those plants that like slight shade. If, however there is considerable shade (as you might get with a solid wall greenhouse), only shade lovers can be put there- but once again there are lots of these to consider. Many houseplants like the sort of lighting you get in this area (and may even be raised there); so, too, do tropical  plants and exotic foliage subjects if warmth and humidity is adequate. Good crops of mushrooms can be grown and, if an area is blacked out, it can also be used for blanching and forcing crops such as chicory, rhubarb and sea kale.

You have staging- what can you use the area underneath for?
You have staging- but what can you use the area underneath for?

I’d suggest that you don’t use the under staging area as a store for general garden stuff (eg plant pots and trays) as these and other ‘junk’ can soon turn into places where pests and diseases will be encouraged. However this area can be useful as a store for tools that are used regularly in the greenhouse, as well as containers of seed and potting compost- as long as these can be effectively sealed (I’ve seen a bag of compost left open in a greenhouse and soon become a home for ants!).

Link: 10 Greenhouses you can build yourself

If you have any gardening questions that you think I might help with, then please email me at nbold@btinternet.com

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and join others by signing up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

The glorious Passion Flower

The glorious Passion Flower

Today’s question concern climbers that won’t flower, specifically Passion flowers and Wisteria. Jimmy Jones of Brighton asks:

‘I’ve a problem with two of my climbers. I have a Passion Flower growing over my front door which grows very vigourously, but produces no flowers or fruit. Likewise I bought a Wisteria a good few years ago and it did not grow for a long time. I fed it and recently it has begun to grow, but still has not flowered. Can you help please?’

The Passion Flower (Passiflora) needs one thing above all else- sunshine. So a south facing wall is really the only place where it will succeed in most parts of the U.K.- it must be open to the sun all day. If your location is right the other issue might be an over rich soil- this can produce a mass of foliage and stems at the expense of flowers, so if you’ve been feeding it perhaps lay off for a while and then make sure you use a feed rich in potassium (e.g.dilute tomato feed), which will encourage flowering.

As for the Wisteria, this is one of those plants that takes a fair while to come into flower. to make the wait even more agonising, it often grows very little in its first year or two. Help to induce flowering by shortening any unwanted long stems in July or August, cutting them back to about 30 cms or to 5 or 6 buds, and prune again in January, shortening all side shoots back to two or three buds, so concentrating the plant’s energy into a limited number of flowering buds. Again, an occasional feed with diluted tomato feed (or another feed rich in potassium) can also coax flowers from reluctant plants.

My own experience from transplanting a Wisteria seedling to my arbour in my Kitchen Garden, is that it’s taken a good five years for it to flower in any profusion, but I think the mild winter and warmish spring have also played a part- below are some pictures of how it looks today. I’m gradually training it over the top and sides of the arbour. You might also find  this article about using climbers in the garden useful.

Coincidentally my younger daughter (who lives in a basement apartment in the outskirts of Lisbon,Portugal), has just bought a Wisteria to go alongside a very successful Trachelospermum jasminoides she and her husband planted about 3 years ago (I’m told the fragrance just now is wonderful). I’ve suggested they train it along wires fixed to the walls of their patio garden and as it’s in a container to give it a fortnightly feed of tomato food to encourage flowering. Fingers crossed!

If you have any questions you’d liked answered then email me and I’ll do my best to feature your question and hopefully provide an answer!

My email address: nbold@btinternet.com, and put ‘GQT question’ in the subject line, please.

Old School Gardener

If you’ve enjoyed reading this post and others on this blog, why not comment and also join some other people and sign up for automatic updates via email (see side bar, above right ) or through an RSS feed (see top of page)?

Frog_in_pond_among_aquatic_plants Today’s question comes from a gardener in North Yorkshire. Ernie Uplad of Richmond has just created a new garden pond in an open, sunny spot away from trees and wants some advice about planting:

‘I’m pleased with my new pond but need some help with deciding when to plant it up, the mix of plants to use and how to go about this- can you help, please?’

When to plant?

Well Ernie, you seem to have made a great start with the choice of a good location for your pond. As for planting  now (early spring to mid June) is the perfect time, as the weather is warming up. If you plant to put in some fish (I wouldn’t myself as they tend to eat much of the other wildlife that will inhabit your pond), then it’s important to plant up before you install them as they might go hungry unless you take the trouble to feed them yourself.

What to plant?

Some plants are essential for a pond (whether it’s for ornamental or wildlife value) – oxygenators. These are plants which live almost entirely underwater  and help to maintain an adequate level of oxygen for the other plants, fish and other animal life. They also help to reduce the level of algae, as do water lilies. The oxygenators include Canadian pondweed (Elodea canandensis), which is vigourous; Egeria densa (less vigourous); water Milfoil (Myriophyllum spicatum), with its delightful feathery foliage; and M. verticillatum, also with feathery foliage, and which also likes limy water.There are also plants you should avoid at all costs- the so called space invaders! Here’s a useful guide to these. 

You migth also like to consider ‘marginals’ – these are grown on the inside edge of the pond- here’s a guide to marginal plants. And, don’t forget plants that grow in permanently damp soil- in a bog garden you may have created next door to your pond. Here’s another useful guide to plants for a bog garden.

For planting actually in the pond here is a selection of plants to add height (they all grow up to around 45 cms (18ins) high) and will add other interest:

Water hawthorn (Aponogeton distachyus), with white flowers with dark spots throughout the year

Acorus gramineus ‘Variegatus’, for foliage colour in green and gold

Bog Arum (Calla palustris) with white flowers in summer

Calla palustris ‘Plena’ with double yellow flowers in March- April

Cotula coronopifolia with yellow ‘buttons’ in  July- August

Hydrocharis morsus-ranae, with white-flowered floaters all summer

Mimulus moschatus and M. ‘Whitecroft Scarlet’ with yellow and red flowers, respectively,  all summer

Golden Club (Orontium aticum) with yellow club flowers in May- June

All medium-sized lilies (Nymphaea) in red, white, pink and yellow shades throughout the summer.

How to plant?

Well, let’s take water lilies first.The crowns (rhizomes or tubers) should be planted in a medium to heavy loam with the crown tips exposed and upright- they must not be buried. all other container plants can be planted in the same type of soil and to the same depth as they were at the nursery or when you propagated them, but avoid over rich soils; you can buy special aquatic compost if you like, but by avoiding rich soils  you will minimise problems with algae and weed through raising the nutrient levels in the water. The oxygenators will need to be weighted if this has not already been done by the nursery. Clumps of 6-12 small pieces should be put on the floor of the pool and held in a group by a lead weight. This will keep them from floating to the surface. Natural floaters like Hydrocharis morsus-ranae are simply put on the surface.

How to propagate?

You might in due course want to propagate your own plants and for most water plants this is very simple. you just divide them in the spring after lifting out the containers any plants you  require. Division is achieved by driving in either two handforks (or two larger forks for larger plants) back to back, then pushing the forks apart to prise away the outermost plants in the clump. Do not use the centre crowns; these are the oldest parts of the plant and should be disposed of.

A pond is a fantastic resource for wildlife
A pond is a fantastic resource for wildlife

Further information: RHS guide to aqauatic planting

Old School Gardener

 

 

Herbaceous borders at Peckover House, Wisbech
Herbaceous borders at Peckover House, Wisbech

Now’s the time to set about creating new borders in your garden and I’m grateful to Hyde N. Seik from Plymouth who asks:

‘I’ve seen some wonderful borders at a National Trust property near me. I enquired about these and was told that they are ‘herbaceous borders’. Can you tell me what this means and how to go about creating one, please?’

Hyde, there’s perhaps nothing as quintessentially English as an Herbaceous border (it became especially popular in the late 19th and early 20th century garden), and many of those associated with our great historic houses are some of the best examples around. This is usually a rectangular border (or twin borders with a lawn or other path running between them), traditionally at least 3 metres wide and about 12 metres long, usually backed by an evergreen hedge. The lengths and widths do vary, but the usual dimensions maintain a ratio of 4:1 (length to depth). The border is planted entirely with herbaceous perennials (plants that grow for more than one year and die back above ground after flowering). The border is designed to be of interest when viewed from the front or along its length and looks its best from late spring to late summer.

These days the amount of work needed to maintain such borders – staking of taller plants to provide support, pruning back dead stems and foliage, feeding and dividing the plants every few years- might be too much for many gardeners and so herbaceous borders can be rather smaller and more irregular in shape, or alternatively have a mixture of planting (including evergreen shrubs, grasses, and annuals) to reduce the workload and provide more structural interest during the winter.

Herbaceous borders are usually planted with clusters of each type of plant, in odd numbered groups of 3, 5 or 7 plants- the tallest are usually at the back of the border and the shortest at the front. However, in recent times this approach has been challenged as borders can look more interesting if some taller plants are placed nearer the front of the border; especially if they add height but are not too dominant, such as Verbena bonariensis and many grasses.

The airy stems of Verbena bonariensis
The airy stems of Verbena bonariensis

As your plants are likely to be in the same place for some time, it pays to prepare the soil thoroughly. Remove all weeds, especially the perennial types with deep roots, by digging, hoeing (or you could use a suitable weedkiller such as Glyphosate in the growing season). Then fork the soil to a depth of at least 150mm adding organic matter such as compost or manure, rotted bark, or other manures such as those from hops or mushroom growing. Lime might also be needed if the soil is very acid (peaty) or in generally very poor condition.

This should be applied in autumn or spring, one month before planting or adding organic material, and at least 2-3 months before adding manure (lime and manure should never be applied at the same time). Incidentally, nearly all herbaceous perennials grow well in most soil types, provided they are neither very acidic or alkaline- by manuring and liming regularly, the soil can be kept at a fairly neutral pH, and regular mulching with organic matter will keep the soil nutrient levels up, avoiding the need for artificial fertilisers or feeds.

If possible, leave the freshly dug soil for a couple of months to allow it to settle, then rake over the surface to produce a reasonably fine, crumbly surface.

Whilst you’re waiting for the soil to be readied it’s worth planning the border planting in some detail. Using a sheet of graph paper, draw on it (to scale) the shape of the border (you could of course have begun with an outline plan on paper for this and then scaled this up to create the new border). Then select your plants from a catalogue, book or online information resource which not only describes the plants but gives their height and ultimate spread/width. Think about the different flower shapes, leaf textures as well as colours in composing your border planting plan and also when the plants flower or have other interest (e.g. leaf colour, berries or other fruit) – to ensure a balanced spread of flowering or other interest throughout the seasons.

Allow for the plants to be grouped in clumps of 3’s or 5’s (odd numbers tend to create informal looking groups whereas even numbers tend to lead to a more formal, regimented layout). These groups can be drawn on your plan with a circle guide or compasses and then a line enclosing the group drawn around them. If you use a set of colour pencils or crayons to draw these groups according to their flower/leaf colour it will help give you an idea of the colour scheme you are creating. Other information – height, flowering time etc.- can be written on your plan and help to check the overall design and ensure that there is no period in the year without interest of some sort (this can extend to winter interest created from strong shapes such as evergreens and grasses as well as some herbaceous plants that hold on to their dead flower heads or foliage).

The best time to plant your herbaceous border is in the autumn or spring, although plants grown in containers can be planted at any time, provided they are kept well watered and the ground is not frozen or flooded. If you buy by mail order, the nursery will send you plants at the right time for planting, although the roots will probably have little or no soil on them (‘bare rooted’). If you can’t get them planted on arrival, store them in a cool place in damp, sandy soil or put them in a trench in the garden (so called ‘heeling in’). However, do try to plant them out as quickly as possible provided the ground is workable.

If the plants seem dry on arrival, soak the roots in water for 24 hours; if any are damaged in transit, let the nursery know as soon as possible, so that they can be replaced.

Herbaceous border at Copped Hall, Essex
Herbaceous border at Copped Hall, Essex

Planting is best done with a trowel. Set the plants out in the planting positions on the soil surface and then move them around to make sure they are in line with your plan which should suit their final growing widths. Dig holes under each plants big enough to accommodate the roots of the plant without cramping them. Work from the back of the border (or centre if it is an island bed). Always plant to the same depth as the soil mark on the stems of the plants.

Hoe carefully to remove footmarks, and water in the plants with a thorough but gentle sprinkling. Don’t forget to label each group of plants, as once they die down you may forget where they were – though your reference plan should help with this. Most herbaceous perennials will spread outwards, gradually dying off from the original centre, so every few years these plants will need dividing, repositioning and mulching. And some of the taller ones will need staking to support them, at least in the early years before those around them provide some mutual support.

Old School Gardener

Finding Nature

Nature Connectedness Research Blog by Prof. Miles Richardson

Norfolk Green Care Network

Connecting People with Nature

Discover WordPress

A daily selection of the best content published on WordPress, collected for you by humans who love to read.

Susan Rushton

Celebrating gardens, photography and a creative life

Daniel Greenwood

Unlocking landscapes

Alphabet Ravine

Lydia Rae Bush Poetry

TIME GENTS

Australian Pub Project, Established 2013

Vanha Talo Suomi

a harrowing journey of home improvement & garden renovation

How I Killed Betty!

Mad as a box of frogs? Most probably ... but if I can’t be perfect, then I’ll happily be fabulously imperfect!

Bits & Tidbits

RANDOM BITS & MORE TIDBITS

Rambling in the Garden

.....and nurturing my soul

The Interpretation Game

Cultural Heritage and the Digital Economy

pbmGarden

Sense of place, purpose, rejuvenation and joy

SISSINGHURST GARDEN

Notes from the Gardeners...

Deep Green Permaculture

Connecting People to Nature, Empowering People to Live Sustainably

BloominBootiful

A girl and her garden :)

%d bloggers like this: