- 1). Read the bulb catalog to see which particular variety of spring bulbs bloom in late spring. Daffodils bloom from early spring through late spring. Tulips from mid spring to late spring. Alliums bloom from late spring through early summer. Choose the varieties that bloom in late spring. If a bulb is genetically programmed to bloom in early spring there's little you can do to force it to wait until late spring.
- 2). Count back 45 days from the first average date of fall frost in your area. Consult the local university agricultural extension or master gardener's group to find out that date. Your local plant nursery should know as well. Spring bulbs need about six weeks to grow a sturdy root system before the frost hits and the weather stops the root development.
- 3). Locate the flowers in a spot which will receive full sun from early to late spring. That could be a shady spot in the fall because of the changing of the angle of the sun from fall to spring or because in fall the location is shaded by a deciduous tree that won't leaf out until after the bulbs have bloomed.
- 4). Dig the dirt in that spot to a depth of at least 12 inches. Bulbs are planted twice their height. Tulips are about 2 1/2 inches tall so that means that they need to be planted at 5 inches deep starting at the top of the bulb. The ground below needs to be amended and loosened so their roots can easily penetrate the dirt.
- 5). Add a 4- to 6-inch layer of organic material to the bed and dig it in. Dig a hole for each bulb that is about 12 inches deep and 3 inches wide. Add a sprinkle of slow-release fertilizer to the bottom of the hole per package directions. Refill the hole to the proper depth for the particular bulb you're planting, and mix the fertilizer in with that soil.
- 6). Put the bulb in the hole with the flat end down and the pointed end up. Cover with dirt. Water until the ground is wet about 6 inches down. Natural rainfall of about 1 1/2 inches per week should provide enough moisture thereafter unless there are drought conditions.
- 7). Cover the bulbs with a 3-inch layer of mulch.
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