The expert gardener

Keeping track of your bulbs

Bulbs are cheap, so we should refuse to feel guilty about splashing around quantities of them in our mixed borders. Most can stay where they are planted for years, either increasing or gradually petering out. That said, I have to admit to spending more on bulbs, annually, than on any other kind of plant.

It is important to know where they are when they are invisible, as most are, in the autumn. Otherwise, you may find them interfering with, or being affected by, other ingredients. If bulbs are planted between tall perennials to give early interest, there is no problem. If they are beneath the branches of deciduous shrubs in early spring, where it will later be dark and nothing else will be required, again no problem. I have the bright yellow Erythronium tuolumnense beneath the horizontal branches of the tall dogwood, Cornus alternifolia 'Argentea', whose branches grow in horizontal layers, and they take it in turns to attract attention.

But if you planted one of the broad-leaved Tulipa fosteriana hybrids close to a patch of Helenium 'Moerheim Beauty', which is just a tight cushion of leaves in early spring, the helenium wouldn't stand a chance.

There are some hardy cranesbills that, from a small crown, steadily expand through the growing season. 'Ann Folkard', 'Russell Prichard', 'Mavis Simpson' and the rather late-flowering 'Dilys' are typical. You can take advantage of the space around them early on by planting bulbs that do all their growing before the space is gobbled up - camassias or bulbous Dutch irises, for instance, or any small, early-flowering bulbs such as the miniature trumpet daffodil 'Narcissus minor', blue scillas, chionodoxas or the yellow winter aconites, Eranthis hyemali s.

Rather special and expensive bulbs, such as Allium giganteum, are worth marking with a small piece of cane stuck in behind each of them. Likewise, where we plant two groups of tulips next to each other, we mark the division with a cane. Then, when we lift the bulbs to replace with summer bedding, they're easily kept separate.

If you do most of your border work in spring - March, say - your bulb problem will be reduced in one way, because you'll be able to see where they've already pushed through. On the other hand, this makes it all the easier to put a large foot on them. A good practice is to work on boards laid strategically across the border.

The fact is that mixed borders are swarming with different plants, all making their contributions, and it is our business to keep them all happy. Not easy, but certainly interesting.

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