Originally imported from Holland, spring-blooming bulbs are now cultivated throughout the U.S., notably in the Pacific Northwest and upper Midwest.
Bulbs are largely trouble free; often only the most careless handling results in failure, which makes them ideal for new gardeners.
Though the display when planted off season is not likely to be as good, as long as the ground isn't frozen, you can plant them year around. Ideally, most spring bulbs should be planted in the fall in well-drained beds of half loam and half sand. Planting from September through November allows plenty of time to develop the root systems necessary for early bloomers like crocus and daffodils. As a rule of thumb, the earlier the bulb blooms, the earlier in the fall it should be planted.
Put new bulbs in the ground as soon as you get them. Though durable, the longer they sit the more likely you'll have casualties.
To create a bed, cultivate at least 12–18 inches of good soil in a well drained, sunny location. If the soil tends to be clayey, cultivate more deeply and work in some sand. Where winds are a problem, provide a windbreak.
Use a trowel or bulb digger to create the hole. To achieve simultaneous bloom, plant at the same depth. By coordinating the type of bloom, its planting depth, season, and duration, you can have spring bulbs from January to June.
Though rotted, composted manure is a rich source of nutrients, fresh manure will unceremoniously dispatch your bulbs permanently. Prepare for fall planting in the spring by letting fresh manure simmer through the summer. By fall, it will be a perfect amendment to your bulb garden.
For each bulb, add a handful of bone meal to the bottom of the hole. Make sure bulbs are pressed firmly into the hole to prevent air pockets that may allow the bulb to rot before it becomes rooted. Water thoroughly after planting.
Planting depth is determined by the diameter of the bulb—that is, each bulb should be planted at a depth of 3 times its diameter. For a 2-inch hyacinth bulb, a planting depth of 6 inches would be optimum. It's better to err on the deep side.
Spacing should be approximately 6–8 inches apart for larger bulbs and 3 inches for smaller bulbs.
Plant with an eye to height of each variety. Place taller bulbs in the back and daintier flowers such as scilla or tiny daffodils in the front.
Once you've planted your fall bulbs, there isn't much to do until spring. However, if you live in an area where the winters tend to be very cold, it's a good idea to add mulch once the ground freezes. A mulch of hardwood leaves can protect your bulbs effectively by preventing premature sprouting.
Once danger of hard frost is past, remove mulch carefully to avoid damaging tender growth. At this point, add compost tea to enrich the soil or use a light dressing of diluted fish emulsion fertilizer. This often increases the vigor and size of blooms especially with tulips, which tend to be heavy feeders. When the young shoots emerge, keep an eye out for slugs especially around fritilliaria.
After blooming is completed, the top growth must yellow and mature for 3–5 weeks to allow the bulbs to store energy for another season.
When clearing the bed for other plantings, disturb the roots as little as necessary and heel them in somewhere in partial shade at the back of the garden. Take care to not damage the roots. Some varieties have a short window of opportunity between the time the tops dry and new root development takes place.
Toss out any bulbs that are soft, tiny, or damaged.
If you must store your bulbs, use dry sawdust, sand, or peat moss. Moisture prompts sprouting, so take care to ensure that bulbs are kept in a ventilated but dry location.
Most bulbs can be left in the ground for several years, but eventually they diminish in flower production and size of blooms. Eventually they benefit from division.
Daffodils need to be divided every few years. Some, like grape or wood hyacinths, are prolific reproducers. In some areas, they are relatively invasive and will crowd other bulbs out. Tulips are best replaced with fresh, healthy bulbs every three years or so.
Bulbs are best divided when the tops have yellowed and they have entered their dormant stage. (Lilies don't go dormant, so dig and divide in early fall, then replant immediately. Protect their bulb and roots at all times against drying out.) Save only the largest bulbs.
Small bulblets can be removed from the parent and placed in a nursery garden for several years until they reach a mature size.
If you can, avoid disrupting bulbs out of season. If you do move a plant, you might be successful, but it's equally probable that you could damage the bulb or roots unnecessarily.
For gardening help, a lawn service can take care of the annual chores while you concentrate on your new bulb beds. ContactorNexus has qualified pros ready to go to work for you.