Tips for getting tulips to return next year

If you want tulips, the gardening wisdom goes, you have to plant new ones every fall.

Most tulips make a big spring splash and then peter out. They might not return at all, or they'll send up some puny leaves for a couple of years and maybe a few mediocre flowers before dying out completely.

But there are exceptions.

If you're tired of planting tulips every year, you can choose types and use planting strategies that are more likely to encourage a return appearance. You won't get the same dazzling display as you would by planting yearly, but you'll save yourself some work.

Most of the tulip bulbs we buy have been bred, coddled and specially selected so they're plump and likely to produce a good-size flower. But after that first blooming, the mother bulb breaks into smaller bulbs as a means of reproduction, explained Becky Heath, one of the owners of the Virginia mail-order business Brent and Becky's Bulbs. Those bulblets can't store the energy needed to push out a big flower the next year.

Some types of tulips, however, do a better job of producing vigorous offspring. And all tulips fare better if they're planted in the right spot and given the proper care.

So if you want your tulips to perennialize, here's what you can do:

Their bulbs don't break up as readily, allowing them to make a strong return, Heath said.

"They're kind of like a tulip powerhouse. They're just incredibly strong from a genetic perspective," said Jo-Anne van den Berg-Ohms of the Connecticut mail-order retailer John Scheepers Inc.

This type of tulip produces large flowers on strong stems. They're available in a fairly wide range of colors, including some striped varieties.

Another group that tends to come back well is Fosteriana tulips, also called Emperor tulips, said Tim Schipper of Colorblends, a Connecticut company that sells tulip bulbs in bulk.

The perennializing success of Fosterianas is partly genetic, Schipper said, but it also has to do with their earlier bloom time. Provided the weather conditions are favorable, Fosteriana tulips have a long growing season that gives them plenty of time to recharge their energy stores for the next year, he said.

Another option for encouraging tulips to keep coming back is to plant species tulips, also called botanical tulips. They're smaller, more delicate plants that are closer in appearance to their wild ancestors than the big tulips that have been developed through hybridizing.

Species tulips not only return year after year, but they multiply and form clumps that grow bigger each year, a process called naturalizing. That process happens when bulblets formed by the mother bulb get big enough and split off to produce their own flowers, Van den Berg-Ohms explained.

Species tulips range from about 5 to 12 inches in height, depending on the type. They include species such as Tulipa biflora, a diminutive white flower with a yellow center, and T. praestans fuselier, a multiflowering tulip with a vibrant orange-red color.

Schipper thinks one of the most important keys to perennializing tulips is to change your thinking. Instead of being guided by where you want your tulips to grow, you have to consider where the flowers have the best chance for long-term survival.

"You have to think like a bulb," he said.

Heath said well-drained soil is especially important in summer. The bulbs are dormant then, and "they want to sleep in a dry bed just like I do," she said.

Avoid planting too early, Schipper said. Wait till daytime temperatures are in the 70s and nighttime temperatures are in the 40s, he said — about the time the fall leaf color is at its peak.

Planting tulips deeper in the soil than other bulbs can help keep them coming back. That protects them better from temperature spikes and exposes them to more of the nutrients and other beneficial elements in the soil, Van den Berg-Ohms said.

Heath recommends planting at a depth that's four times the height of the bulb. The ground pressure is higher at that depth, which tends to keep the bulbs from breaking apart, she said.

If the fall has been dry, water the plants immediately after planting to get the roots started, she said.

After the first year, though, fertilizing can improve their vigor, she said. She recommends sprinkling an organic fertilizer three times a year: in fall, in early spring when the sprouts first appear, and later in spring when the flowers start dying back. Choose a fertilizer that's higher in phosphorus than nitrogen or potassium, she said.

Or forget about fertilizer and just apply compost. That's Heath's preference.

Make sure the bulbs don't get too much moisture in summer, when they're dormant. Schipper said excess moisture is often the problem when water-loving annual flowers are planted in the same space after tulips finish blooming. As gardeners water the annuals through the summer, they drench the tulip bulbs and can cause them to rot.

Van den Berg-Ohms also recommended against cutting the larger types of tulips to bring into the house. Removing their stems depletes their energy-storing ability, she said. Instead, wait until the flowers finish blooming and start dying back, and then cut off the flower heads about 1 inch below their base so the plant doesn't put its energy into seed production.

The smaller species tulips don't need deadheading. In fact, Heath said, leaving the flower heads in place allows the seeds to drop and possibly produce more plants.

Let the foliage die back before removing it, which can take as much as eight weeks. It's not all that attractive at that stage, but don't braid it to make it look neater, the experts said. You want to leave as much of the foliage exposed to the sun as possible, so the plants can use photosynthesis to recharge the bulbs.

Trouble with deer and voles? Heath recommends Plantskydd, a repellent made from dried blood.

In the end, nature has the final say on whether your tulips will return.

A hot spell in spring can cut short the growing season by causing the flower bud to open before the plant reaches full height, Schipper and Van den Berg-Ohms said. That reduces the plant mass left to produce next year's food through photosynthesis.

And some sites just have more favorable conditions than others. Tulips might return year after year in one part of your yard but not another, Schipper said. He's always getting calls from people who want to plant the kind of tulips that bloomed every year in their grandmothers' yards, but it's probably the microclimate that was responsible, not the type of tulip.