HORTICULTURE
The Basics of Bulbs
by Julie Barnes
Patience is one of the hardest gardening tools to use, particularly when it comes to planting spring bulbs now for next year's bloom. Here's a primer on these spring flowers.
Planting time – It's best to plant your bulbs when the soil temperature at the bottom of the bulb holes is about 60°F- generally, between mid-September to mid-October in the North and mid-October to the end of November in the South.
Planting depth – The general rule is to plant bulbs three or four times as deep as the bulbs are tall. For instance, if you have a 2-inch tall bulb, plant it 6 to 8 inches deep.
Soil – Most spring-flowering bulbs prefer light, loose soil. To help your bulbs along, work compost or organic matter into the soil. Another tip: Place a layer of sand at the bottom of the planting hole to aid drainage.
Exposure – Most spring-flowering bulbs prefer a sunny spot or at least a half days' worth of sun. Without enough sun, the leaves won't produce enough energy for the bulb to continue blooming prolifically. Remember that deciduous trees usually leaf out before the foliage dies back naturally, so it might not work to plant bulbs beneath dense trees.
Care – Once the bulbs are planted and watered in well, there's not much you need to do in the autumn. After the soil has frozen, a layer of mulch will help. When spring comes, be sure to deadhead the faded blossoms and allow the leaves to die back naturally.
Hardiness – Different bulbs are hardy to different zones. Even different species of the same kind of bulb (for example, various species of daffodils) have different hardiness ratings. As a very general rule, most of the common spring flowering bulbs are hardy in Zones 3 to 8.
Types –Tulips (Tulipa spp.) and daffodils (Narcissus spp.) are easily the most common spring-flowering bulbs. Don't forget about some of the other delightful beauties, though. They include squills (Seil/a spp .), snowdrops (Galanthus spp.), crocus (Crocus spp.), hyacinths (Hyacinthus spp.), grape hyacinths (Muscari spp.), alliums (Allium spp.), glory of-the- snow (Chionodoxa spp.), and puschkinia (Puschkinia spp.).
Naturalizing – Many bulbs, such as daffodils and Siberian squills (Scilla siberica) can be naturalized, or planted in informal groups outside of planting beds (in areas such as the lawn or in a meadow). Over the years the bulbs will multiply readily and look like they've been there forever.
Forcing bulbs – You can force most spring-flowering bulbs to bloom inside. Some of the easier bulbs to force are daffodils and hyacinths. Most bulbs need at least 12 weeks of 40 to 50°F temperatures before they'll bloom, but some, such as amaryllis and paper-white narcissus, don't need any cold at all.
Replanting – As much as we'd like to give forced bulbs a home in the garden, it's generally not worth the effort to plant them. Not only are their internal schedules off, but the stems are usually too short to plant them at the depth they need.