Bulbs are a favorite among gardeners. The appearance of cheerful, brightly-colored flowers like tulips, daffodils and crocuses marks the end of winter and brings the promise of spring. Bulbs can be trickier to plant than seeds, but they're well worth the extra effort.
Choosing and Storing Bulbs
Look for bulbs that are firm and large. Softer bulbs may not grow as well as firmer ones, and larger bulbs are generally heartier and produce more blooms. Tears and cracks in the outer skin are fine, but check for cracks in the flesh. Also look out for mold, mildew and soft spots.
Because they are made up of fleshy plant matter, bulbs can rot easily, especially if they are exposed to moisture. It's best to plant bulbs as soon as you buy them. If that isn't possible, store them in a cool, dry place and check them for firmness before you plant them.
When to Plant
Summer-blooming bulbs should be planted as soon as the ground is thoroughly thawed and moderately warm, which, depending on where you live, can be from early April to late May.
Spring-blooming bulbs should be planted about six weeks before the first frost. Since the occurrence of the first frost is difficult to predict in some places--especially those with mild winters--follow the recommendations for your agricultural zone. Gardeners in zones 2 and 3 should plant in September, zones 3 and 4 in October, zones 5, 6 and 7 in November, and zone 8 in December. You can find your zone on the U.S. National Arboretum's USDA plant hardiness zone map. Go to www.usna.usda.gov/Hardzone/.
Prepare the soil before you plant. Use a spade, shovel or pick ax to work the soil until it's loose and soft. You can add some rich organic matter to the soil at this point, but fertilizer isn't recommended--it can burn the tender roots.
To deter garden pests, provide insulation, prevent premature growth and establish a deep root system, bulbs must be planted far deeper in the soil than seeds. Your bulbs should come with instructions about planting depth, but a good rule of thumb is the larger the bulb, the deeper it should be planted. Small bulbs should be planted 4 to 5 inches deep, while large bulbs should be planted 6 to 8 inches down.
There are two ways to dig holes for bulbs. For tidy formal rows you can use a bulb planter, a cylindrical tool that punches holes in the earth that are just big enough for one bulb. For fuller, more colorful plantings, dig a large hole or a trench with a spade and plant several bulbs at once. Bulbs should be planted with their pointed side up, 6 to 8 inches apart.
Consider planting early spring, late spring and summer-blooming perennials around the bulbs. This way, you can have color in your garden throughout the growing season. Mark where you have planted the bulbs so you don't inadvertently dig them up.