Gardening: Why you should let sleeping flowers lie

They are not dead, just dormant: bulbs need to be treated with care. In the annual rush to plant for spring, Ursula Buchan offers a guide

Autumn bulb-planting is one of those annual rituals, like pruning clematis or picking the apple crop, which measures out the gardening year. Its place in my horticultural calendar is assured, both because no garden can ever be said to have too many spring-flowering bulbs and because their method of growth, and the effects they create, seem almost magical.

Every year I plant several hundred bulbs (also corms, tubers and rhizomes, to be strictly accurate) in grass, in borders and in pots, and I will continue to do so until the Crack of Doom, even though their capacity to perpetuate themselves makes them some of the most enduring plants in the garden.

However, the moment for the inevitable bulb-planting binge can find me regrettably unprepared. Instead of passing an unhurried evening in midsummer filling in an order to a specialist mail-order firm, which is what I like best, I spend an early-September afternoon scouting around garden centres.

In normal circumstances, no one could accuse me of being a touchy-feely kind of girl, but I rather let myself down when I go buying spring-flowering bulbs. Regardless of the strange looks I attract, I touch and feel like anything, determined not to waste money on bulbs which rot or shrivel after planting.

After all, flowering bulbs are living things. At the time of sale they are not dead, only sleeping. Almost without exception, they have a period in the year when they lie dormant. Their shoots die down after flowering and seeding, and their roots shrivel, but within, next year's flowering shoot and leaves are forming. If you cut open a daffodil bulb you can see the embryonic leaves tightly folded, ready to unfurl and elongate once conditions are right for growth.

While they are in this dormant state, bulbs are surprisingly vulnerable. High temperatures will shrivel them up, while high humidity will leave them open to rot. Wherever you buy them, it makes sense to take careful account of how cool and dry the atmosphere is, and how well-protected the bulbs are from direct sunlight. If I am hot and sweaty, I am sure they will be too.

Some bulbs are more vulnerable than others. For example, anemones are old toughies whereas fritillaries are naturally soft and fleshy, so I buy the latter only if they are stored loose and separately in sawdust, rather than jumbled together in plastic bags. The same goes for summer- flowering lilies bought in the spring.

Before I part with my money for any bulb, I test its solidity by pressing a finger against the baseplate, from which can usually be seen one or two old shrivelled roots, and also squeeze the neck of the bulb, as one might do a cooking onion in the supermarket. I avoid any that show signs of mould, bruising, pest damage or bad cracking, and buy those with tunics (such as tulips and bulbous irises) only if they are intact.

As for those bulbs such as winter aconites and snowdrops which re-establish themselves quickest if they are dug up "in the green" (just after flowering), I think it better to do swaps with a kind friend, or buy them in pots in the spring, rather than acquire them dry now and risk losing the flower in the first spring.

All my care in choosing is so much wasted time, however, if I leave them lying about at home before planting. The sooner bulbs go in the ground once acquired, the better. Time presses in September. Now that most of us have had some rain (and northern gardens have had rather more than is ideal) and, in theory at least, the soil is still warm from summer sun, it is best to get bulbs underground as soon as possible so that roots will grow quickly and anchor before the winter.

The exceptions to this are tulips which, because their growing shoots can easily be damaged by winter frosts, are usually planted in November. No spring-flowering bulb likes a soil that becomes waterlogged, so heavy clay soils should be lightened with plenty of grit. If manure or compost is dug in (and the larger bulbs such as daffodils and fritillaries appreciate it), it should lie below the level of the bulbs. For most smaller bulbs, a handful of general fertiliser per square yard is sufficient.

The important consideration (and it is not as barmy as it sounds) is to ensure that the bulb is planted the right way up, or it will either fail or waste precious time turning itself round. Bulbs such as daffodils obviously have a growing point and a basal root plate, but the top and bottom of some corms and tubers, such as cyclamen, are harder to divine. Look for any residual roots or incipient buds.

The basic rule of thumb for achieving the right planting depth is to have the top of the bulb twice its height below the surface. Common sense dictates that very large bulbs must be protected from drying out and need to be anchored deep in the soil, but it is not so vital for small bulbs, such as snowdrops, which often work their way to the surface when overcrowded, and still manage to flower. Crocuses even have the capacity to pull themselves up or down, by means of "contractile" roots, to the level they prefer.

As I said, magical.