Beautiful spring tulips, hyacinths, daffodils and crocus require planning ahead and planting bulbs in the fall to early winter, said Michael Arnold, Ph.D., director of The Gardens at Texas A&M University and professor of landscape horticulture in the Texas A&M College of Agriculture and Life Sciences Department of Horticultural Sciences.
For Arnold, planting bulbs in the fall to brighten the spring landscape has been a family tradition since he was a kid. He has bought bulbs for his mother’s October birthday for the last 50 years.
Taking flowers from bulbs to blooms is simple, Arnold said. For classic spring bulbs like tulips, hyacinth and crocus, purchase them in the early fall, give them the chilling time they require, plant them and wait to enjoy their spring display.
Time to plan
The height of bulb season runs from mid-September through October. The earlier you order, the better the variety selection and availability.
“If buying online, make sure you’re buying from a reputable nursery,” Arnold said. “They will have stored bulbs properly before shipping, and they will usually arrive in good shape. All you really need to do is put them into a refrigerated setting, and they should be fine until it’s time to plant.”
If not stored in optimal conditions, bulbs can become dehydrated or damaged or can sprout prematurely. If they sprout before they have been chilled, they won’t flower.
Time to chill
Because of Texas’ mild winters, traditional spring bulbs like tulips, crocus, some narcissus and the Dutch hyacinth require six to 10 weeks of chilling before planting.
“They function as annuals in much of our region,” Arnold said. “They usually don’t come back the next year because they don’t get enough required chilling hours in our winter soils, especially the further south they are planted in Texas.”
If storing bulbs in a refrigerator, he said to keep them away from any produce that will give off ethylene — don’t put them in the same drawer as heads of lettuce, tomatoes or apples. Place the bulbs in a large, sealable plastic bag to keep them from drying out.
Time to plant
Arnold recommends storing the bulbs in a refrigerator or other cooler until about the first part of December. Then, plant them in the soil during the early to mid-December cooler temperatures to establish root systems to bloom the following spring. Nighttime temperatures should be under 50 degrees for several weeks.
Some general rules for planting bulbs include:
- Plant in well-drained soil.
- Plant the pointed side up — the growing side faces up, and the rooting side faces down.
- For planting depth, figure about twice the height of the bulb. If the bulb is 2 inches, plant it 4 to 6 inches deep. If it’s a 1-inch bulb, plant it 2 to 3 inches deep.
- Plant in groupings of five or more for the best display.
- In terms of fertility, bulbs usually respond well to a general-purpose complete fertilizer.
- Firm the soil around the bulb and water well to settle the soil.
Time to share
When annual flowers have faded in the spring, remove and discard or compost them.
But some flowers, such as cultivars of low-chilling daffodils, paperwhite narcissus, Summer Snowflake and grape hyacinth, are good examples of spring-flowering, naturalized perennials that can return year after year, Arnold said. They don’t have as stringent cold requirements to stimulate bloom and regrowth.
For perennials, after spring bloom, Arnold said to allow the green, above-ground foliage to die back naturally. The yellowing leaves feed the bulbs for next year’s flowers. Once they die back, you can rake them out or cut them off.
“That’s why it’s good to interplant spring bulbs or flowering plants with perennials like daylilies to provide foliage in the summer while you’re waiting for the unsightly leaves to go away,” Arnold said. “Then you can dig those bulbs up, separate them, and share some with your friends.”
Bulbs for generations
After several years, naturalized bulbs will become crowded. Blooms will reduce unless the bulbs are divided. Arnold said to dig them up during the summer dormant season, divide them, plant the removed bulbs in new spots or give them to friends and family.
Some hardy perennials can survive for generations, Arnold said. For example, he recently received some daffodil, narcissus and daylily bulbs his brother dug up from their great, great, great grandparents’ homesite. The house is long gone, but an acre of daffodils reappears every year.
Arnold plans to plant some of them at his home and in The Gardens this winter.
