Growing Flower Bulbs
If you plan ahead, you could have bulbs flowering in your garden nearly year-round. Bulbs can be left to naturalize in lawns or to carpet shaded woodland areas in spring. They also provide the early season’s show in your borders, before herbaceous plants have stirred into growth, and make excellent companions for perennials and deciduous shrubs, filling the gaps between these plants.
Bulbs are easy to grow, as long as you follow a few simple rules. In the wild, most bulbs grow in climates with hot, dry seasons, and prefer light, free-draining soils in full sun. Bulbs from woodlands need moist, rich, but free-draining soil, and dappled sun or part shade. In short, if you know where your bulbs come from, it’s easier to provide a home for them in the garden. For example, woodland bulbs, such as bluebells, colchicums, cyclamen, and snowdrops, come into growth when the weather is sunny and wet—this will be when overhanging trees are leafless, since the foliage reduces the amount of light and rainwater reaching the bulbs. The bulbs come into leaf, flower, and set seed between late fall and spring, and are dormant again by the time the trees are in full leaf.
What Is a Bulb?
It can be confusing when you discover that the word “bulb” is often used as a blanket term for any plant that has an underground food-storage organ. So as well as true bulbs (as in snowdrops and lilies), there are three other forms: corms (crocuses), rhizomes (irises), and tubers (cyclamen). Each type of bulb has evolved to cope with distinct growing conditions.
- True bulbs are made of leaves layered as in an onion, with a papery skin. Lily bulbs are looser in form, and lack a papery skin.
- Corms are the thickened base of the stem; they have 1–2 buds at their apex. Tiny cormlets may grow around the base.
- Rhizomes are swollen stems, which usually grow horizontally near the soil surface, and have several buds along them.
- Tubers come in two types. Root tubers (as in dahlias) have buds at the stem base. Stem tubers (as in cyclamen) have surface buds.