Sharon Hull, This Week in the Garden

Inexperienced gardeners are sometimes surprised and dismayed in spring, when they discover that the flowering bulbs they see blooming all over town cannot be purchased for their own gardens, that they missed the opportunity during the previous fall.

So every autumn in this column, I remind readers that spring-blooming bulbs are arriving now and filling up the garden center bins, and that to have those luscious spring blooms, and the widest selection, the bulbs should be purchased and planted in fall. (I’m using the term “bulb” here to mean actual bulbs, corms, rhizomes and tubers.)

Though pots of bulbs are available in spring, you’ll not only pay a premium price but may be buying bulbs that have been forced into bloom. Such bulbs are often exhausted by the forcing process and may not bloom well again for years, if at all. It is far better for the best flowering to buy dormant bulbs to plant in fall.

Though I am recommending that you purchase bulbs now, before the choices are picked over by eager gardeners, I am not recommending that you plant them quite yet. (Bearded iris is an exception: plant iris rhizomes immediately.) In our long mild autumn, bulbs planted now may come up immediately because the ground is still warm. Though fall sprouting doesn’t seem to cause long-term harm for most bulbs, it does make the foliage vulnerable to damage from slugs and snails, or from heavy pounding rains.

In our area, most bulbs are best planted in late October or November, after the ground has cooled down, and just as the rains begin. Until then, store them in paper bags or cardboard boxes (plastic can cause rot) in a dark cool dry place. The refrigerator is ideal though you need to keep them away from fruits like apples and avocados; the ethylene gasses such fruits produce while ripening can cause damage to the developing flower buds inside your bulbs. And DO NOT store in the freezer. The near-zero temperature in your freezer will kill your bulbs.

In order to bloom properly, some bulbs need to experience a “winter” which our mild climate does not supply. Among these are tulips, true hyacinths and most crocuses. Here is where the refrigerator is handy: refrigerate these cold-requiring bulbs for eight weeks or more. If not chilled, such bulbs may have extremely short flower stems with the blooms hidden in the foliage, or they may not flower at all. If started now, there is adequate time for this essential chilling period. Narcissus, grape hyacinth and most other bulbs are not quite as picky, and will bloom properly with the chilling our winters provide.

If you choose to store your bulbs in a shed or the garage, make sure rodents cannot access them. Narcissus or daffodils are usually ignored, but other bulbs are attractive food to many animals.  This means that if you have gophers in your garden, you should plant most bulbs in gopher baskets. (Though the pests don’t usually eat narcissus, they may move them around, so that your design scheme is ruined and in spring, you find them sprouting in strange places.)

Choose bulbs that are firm and free from deep cuts or soft spots. They should feel plump, and the basal plate should be solid and firm. If you have a sunny garden with good drainage, you can grow most of the spring blooming bulbs but if your garden is shady, your choices are fewer.

Grape hyacinth (Muscari), snowdrops, the smaller fritillarias, some lilies and most scillas (wood hyacinth) are tolerant of partial or bright shade. Nearly all have low-water needs so fit readily into drought-tolerant landscapes. And if you like the looks of several flower types blooming together, check out one of the mixed bags now available. An example: you can buy a bag containing bulbs of yellow narcissus and purple grape hyacinths, all with the same expected flowering time.  Planted together in a pot, the effect can be gorgeous.

Garden tips are provided courtesy of horticulturist Sharon Hull of the San Lorenzo Garden Center. Contact her at 831-423-0223.