When to Plant Spring Bulbs:
Zones 2 to 3: SeptemberZones 4 to 5: OctoberZones 6 to 7: NovemberZone 8: December
How Deep to Plant Your Bulbs
To determine planting depth, go by bulb height. Dig a hole three times deeper than the height of the bulb. So for a bulb 1 inch tall, go 3 inches deep. It also matters which way you place the bulb into its hole. Inspect the bulb for either a point or tiny roots. If you find a point, that’s the top. If you find roots, that’s the bottom. Place the bulb in the ground such that the top points skyward. If you can’t make out a top but do find roots, place the end with those roots at the hole’s bottom. When planting, sprinkle bulb fertilizer in the hole and water (but don’t flood the area, which causes bulb rot). Spring’s the time when spring bulbs need the most moisture. If you aren’t getting much rainfall, it’s up to you to supply water from the time you first spot flower buds until two weeks after flowering. Ensure that the water is penetrating down to bulb-level underground. Most types of spring bulbs grow best in well-drained soil in full sun. After flowering finishes, deadhead them (remove the dead flowers), but leave the foliage alone as long as it remains green. Your plants are gaining nutrients through photosynthesis during this time. You’ll deprive them of nutrition if you rob them of their leaves. Usually, the leaves don’t look very good after blooming, but this is a case where practicality trumps aesthetics. Disguise the unsightly leaves with the fresher foliage of perennials by interplanting the latter among your spring bulbs. The perennials will start to leaf out fully just as the bulbs’ leaves are beginning to look ratty. When bulbs peter out, divide them after the leaves turn brown. Fertilize with compost and bonemeal every fall. Now that you know when to plant spring bulbs and how to care for them, learn about the best choices available, by color:
Its flower head is big (7 inches), perfectly round, and densely packed with tiny, purple flowers. That of Allium schubertii is bigger, but Ambassador’s is denser. It’s one of the tallest alliums (46 inches).
Even after flowering, an attractive, dried seed-head remains behind, offering interest in summer. Poisonous plants for pets, they are, happily, also deer-resistant bulbs. People may not think immediately of reticulated irises (Iris reticulata) when mention is made of irises, since the flower is smaller than most. But they make up for this by being early bloomers. The delicacy of the flowers is also valued, but they aren’t fragrant. These plants are shorter than most irises (9 inches). Although they are classified as corms, crocuses such as Crocus vernus are grouped with spring bulbs for practical purposes. Crocus vernus is one of the earliest spring-bloomers. But Crocus sativus and the similar Colchicum autumnale bloom in fall. Besides yellow, common colors are purple, white, and lavender. For bigger plants, grow giant snowdrops (Galanthus elwesii), which reach 1 foot tall. So do the similar spring snowflakes (Leucojum vernum). Don’t confuse grape hyacinth (Muscari botryoides) with Hyacinthus orientalis. Both smell great, but grape hyacinth bears tiny flowers in clusters reminiscent of grape clusters. Height is 6 to 10 inches. Spanish bluebells (Hyacinthoides hispanica) are lavender-blue rather than true blue. They also come in white and pink. Height is up to 16 inches.
Fosteriana (early-flowering)‘Triumph’ (mid-season bloomer)Lily-Flowered (late-flowering)
At 3 to 4 feet tall, crown imperial (Fritillaria imperialis) is the tallest spring bulb. But it’s also the most short-lived. Besides orange, it flowers in yellow or a reddish color. The plant stands 4 to 6 inches tall. Grow it in full sun to partial shade. It is cold-hardy all the way up to zone 3. The flower is mainly a light color (almost white), but a blue stripe runs up the center of each petal.
