Layering shrubs and the joys of bedding plants

Pretty, cream-edged leaves of Castanea sativa Argentomarginata

It has been so hot lately that for light relief I have been doing some weeding in the shady area I call the Oriental or Woodland Garden. One of the delightful plants we grow there is not at all oriental, a variegated Chestnut, currently a very healthy looking bush. Removing weeds from around it I considered trimming up some of the lower branches but on reflection decided to use them as layers. I really like layering as a technique, mostly because it is completely fool-proof, and we have propagated many plants in the garden this way.

My experience with layering goes back to my youth, when I worked at the Royal Gardens at Windsor. A large proportion of these gardens were developed under mature Oak trees and as a result leaf-raking was a major activity in our lives for six months of the year, or so it seemed. Some of these leaves were taken to stacks to slowly break down, to be put back into the ground as soil improver. Huge quantities were just raked onto the shrub beds, where they acted as wonderful mulch. This mulch also provided ideal conditions for shoots to root, having been covered in the process. I would often find nicely established layers of rare and unusual Rhododendrons and other shrubs around the gardens……one or two of these found their way back home to Cornwall.

Layering is a long-established, if slightly old-fashioned, commercial propagation technique for a number of plants, still practised for species which are slow or difficult to root. It is useful when a nurseryman requires only a few specimens of a particular tree or shrub, or when large plants are wanted quickly. Layer beds may be established to achieve this, producing plants by systems such as Simple, French, Serpentine or Tip Layering, depending on species. Fruit tree rootstocks are commonly produced by Stool layering.

Marigold Golden Puff from Suttons, next to self-seeded Verbena bonariensis

Here at the Academy, I laid down a shoot of our Chestnut into a hole I had dug close by, bringing it up again in a way that formed an elbow approximating a right angle. Soil was packed down on top, this bending interrupting the flow of sap and inducing root formation. In the past I have done the same with Cotinus Royal Purple and Viburnum x. hillieri ‘Winton’, and used other forms of layering with Wisteria, Rubus and many other subjects. I also use it to train plants like Lavender and Santolina, bending and earthing-up a branch to push a shrub in the direction I wish. These layers could be removed and sometimes they are – they make nice presents – but often they are just left in place to increase the size of the shrub.

A pot full of Coleus Kong

We have grown large numbers of bedding plants this year, knowing the garden would be disturbed by the installation of the swimming pool. These are now starting to flower, later than in the village streets and park, but they have better facilities than we do. I like to grow small numbers of a wide range of bedding so our annual parcels from the likes of Suttons and Thompson& Morgan are always an event. Gazania Daybreak Tiger Stripe (Suttons) is one of the earliest in flower in the front garden while Antirrhinum Axiom and Busy Lizzie Double Carousel from T&M have just started in the pool-side bed at the back. Sweet Pea  Prima Ballerina, grown over a metal climbing frame, has kept the house in flower for a while now. Also from T&M, Coleus Kong mix is at its best with us when well fed in a pot, but less good in the poor soil near the pool. Sutton’s Marigold Golden Puff is just beginning to look impressive, alongside the ornamental, purple-leaved Millet Purple Baron. There will be many more to report on as the season progresses.

Spring gardening in France -2012

Such a wonderful time of the year – spring – but it’s never easy to say when it has started and when it has finished.

Officially, the four seasons are determined by changing day-length, which is currently increasing by more than 20 minutes every week. This change is determined by how the earth orbits the sun and the tilt of its axis. On the first day of spring—the vernal equinox—day and night are each approximately 12 hours long; the actual point of equal day and night occurs in the Northern Hemisphere a few days before the vernal equinox. The sun crosses the celestial equator going northward; it rises exactly due east and sets exactly due west. The first day of summer—the summer solstice—is the longest day of the year, when the sun reaches its most northern point in the sky at mid-day. After this date, the days start getting shorter.

The first Primrose of spring

So, spring starts officially on Tuesday March 20^th and ends Tuesday June 19^th, but here in the centre of France the plants and birds beg to differ: they are pushing on regardless. We are having our lunches in the garden now, and the resident lizards are popping out at regular intervals to see it we drop anything. In the warmer gardens Primroses have started flowering and up in the greenhouse in the loft, seeds are germinating like there is no tomorrow. It’s all very exciting.

As usual I am growing more than we can cope with and as seedlings are ready they come down from the loft to the dining room windowsill and from there to a bench I have set up in the cabin by a big, south facing window. I am leaving the Begonias upstairs in the warm for a while yet but we have so far moved on a nice little selection of plants:

• Geranium Moulin Rouge
• Gazania Daybreak Tiger Stripe
• African Marigold Golden Puff
• Aubergene Amethyst
• Antirrinum Axium and
• Coleus Kong mix

Having completed the marking of student assignments for the day I have a little time to sow a few more trays or pots of seed and perhaps move one or two more down. Impatiens have germinated well and I am hoping my home grown plants will be successful. Impatiens downy mildew – Plasmopara obducens – is a new disease, found for the first time in the UK in 2003, which perhaps arrived on imported commercial propagation material (seed or cuttings). Controls have since been ineffective and 2011 was saw the biggest UK outbreak yet. While wholesale propagators like Ball/Colegrave are continuing to grow Impatiens in 2012, Thompson and Morgan will not be offering young plants and the DIY chain B&Q will not be selling their usual 20 million or so. They are encouraging customers to buy Petunias, Geraniums and Begonias instead but I refuse to be put off and will grow my own. No doubt I will be unbearably smug if all goes well and blame foreign imports if it doesn’t!

For those of you who follow these things, my plant of the week on Pinterest is the Daffodil, which have begun to flower again after last month’s cold spell.