When to planting bulbs? Although September is still a warm summery month, the first fingers of autumn are gilding the leaves on the silver birches; painting the holly berries, the apples, and the shining blackberries in the hedgerow. It’s time to start planning another spring.
All those catalogs of new plants and bulbs ordered last month will have arrived. Decisions will have to be made. What to plant where? Which bulbs to plant in that gorgeous new container? And how to plant them? Most good nurseries will give an indication of the most suitable situation for their plants, but it’s easy to overlook the bulbs.
Daffodils and Narcissi are Easy-Going
And will thrive and flower for several years in most situations except the extremes of drought and wet, before their clumps will need splitting. The shorter varieties are perfect for containers, and they are lovely planted through the herbaceous border. At this time of year the temptation is to plant these smaller bulbs at the front forgetting that next spring all those tall perennials will just be clumps of leaves at ground level.
So plant the bulbs in ribbons running through to the back of the border, or dot them about using a mix of different varieties, and intersperse them with pulmonarias, primroses, and hellebores. They will all enjoy the over-familiarity of ultimately taller neighbors who will provide them with the sort of summer shade they would have in the wild.
These days many people who naturalise narcissi in an area of grass choose our native daffodil, Narcissus pseudonarcissus ‘Lobularis’, or the Tenby Daffodil, N. obvallaris. These smaller flowers are more in tune with spring meadow plants such as the emerging cowslips and Snakeshead Fritillaries (Fritillaria meleagris). Rich moist soil is ideal for Lady’s Smock (Cardamine pratensis) which will very gently and slowly make more of itself.
Crocus Prefer a Light Soil
Mice and squirrels prefer crocus. If they are a problem try planting the corms in wide, shallow ‘pans’ that look like a flan dish with holes in the bottom. Protect the pans with netting for the winter, put them somewhere prominent while the crocus performs, and then plant them out in the garden for next year. Usually, our little furry friends leave them alone then, but a temporary piece of netting over the top will thwart their intents allowing the corms to root out and get a stronger hold in the soil.
Tulips relish the sun and also perform best in well-drained soil. Their vibrancy re-ignites the garden after the coy pallor of early spring. A jewel-rich combination of Venetian colors: reds, oranges, purples, and blacks set the garden alight. A big terracotta pot planted with blood-red T. ‘Abu Hassan’ and brown wallflowers is dramatic. And out of shouting distance, a large pot of the pink and white, peony-flowered ‘Angelique’ tulips is pure Hollywood.
Spring Plants for Shade is Altogether Quieter and More Polite
Many of the little blue bulbs such as scilla, chionodoxa, or the paradoxically blue wood-anemone, A. nemerosa ‘Bowles Purple’, are quite at home under the trees with snowdrops and Dog’s Tooth Violets (Erythronium dens-canis). Plant them among deciduous ferns then as the bulbs fade the crisp green crosiers will unfurl to take their place. If you have control of your molluscs, there is a startling new hosta with green leaves and bright red stems, H. ‘Red October’.
But if the slimy ones are in the ascendant, you could pop in some of the shining yellow grass Hakonechloa macra ‘Aureola’. It loves the shade. Available this autumn is a new form with emerald-green leaves that turn scarlet in autumn, H. macra ‘Nicolas’.
Or you could trick Mother Nature. Bulbs that are sold in autumn will all flower the following spring. Their embryonic buds are already formed when you plant them: they have no choice but to do what comes naturally and flower. At Barnsley House near Cirencester, the one-time home of the late plantswoman Rosemary Verey, there is a much-photographed laburnum tunnel.
Lining the pathway beneath the laburnum there are rows of mauve Allium aflatunense (A. hollandicum) whose flowering coincides and contrasts so well with the golden Laburnum. But visitors do a double-take as they realize that the sun-loving allium is by now completely in the shade and yet in full flower. Rosemary Verey would replenish the old alliums annually as they ceased to flower, with fat new bulbs, pregnant with buds, to startle next spring’s visitors.
BOX on Planting bulbs
As a rule of thumb plant bulbs at least twice the depth of their height.
Tulips should be planted at least 15cm (6ins) apart to avoid Tulip Fire.
Ideally, most bulbs should be planted in September, and tulips in October.
But if the borders are still crowded, pot up the bulbs pro-tem and plant them out in November. Their roots will have formed and they will flower at the correct time.
Protect the potted bulbs from marauding mice.
Take cuttings of half-hardy perennials at the beginning of the month. They will have rooted by October and can be potted up and kept frost-free over the winter.
Keep some of the bigger runner beans on the vine to save the seed for next year. Dry them out in the greenhouse or garage and store them somewhere cool and dry in a paper envelope.
Clear the ground and plant out biennials where they are to flower next year.