Katherine Grace Endicott
Last spring, I leaned over the edge of a picket fence in Leiden, Holland, admiring a row of bright-yellow, star-shaped tulips -- Tulipa tarda. They were identical to bulbs planted there by Carolus Clusius in 1593. He added a picket fence as an afterthought to keep the bulbs from being stolen.
Despite the fence, the tulip bulbs were stolen. The Dutch, however, weren't the first to risk their necks for tulips. The tulip had long been beloved by the Turks, who collected them from their wild steppes and honored them with festivals.
An Austrian ambassador to the Ottoman Empire acquired a few tulip bulbs in the mid-1500s and passed them along to his friend Carolus Clusius, who grew them in his university herbal garden. What followed was the worst case of gardening mania ever known. The Dutch could not get enough of these small treasures. A single bulb could cost as much as a house. When tulipmania ended in 1637, many garden fanatics were financially ruined.
The Dutch, however, are a very practical people and before long, bulb growing became a national industry. Many of the growers I visited in Holland were family concerns established centuries before. These growers produce 80 percent of the bulbs for the world market -- some 270 million tulip bulbs each year go to the United States alone.
Why do we buy so many tulip bulbs? Aside from their astonishing beauty, it's because we can't manage to keep them blooming year after year. Since the tulip is a perennial, it should come back each year.
And so it does on the steppes of eastern Turkey where the winters are cold and the summers hot and dry. But in our mild-winter area we're lucky to see a repeat bloom from most tulip bulbs.
Fortunately, the bulb experts in Holland had some advice on how Northern California gardeners can increase the odds of their tulip bulbs blooming again: Choose bulbs that are marked for naturalizing.
Species bulbs and their hybridized strains are excellent -- including the bulbs first grown by Carolus Clusius: Tulipa tarda `Keizerkroon' and Rembrandt tulips.
Other good choices are the Darwin hybrids in red, rose, orange, yellow and two-tone combinations.
TULIPS -- Botanical Name: Tulipa
-- Common name: tulip
-- Site preference: Full sun. Remember that deciduous trees will not have leafed out yet when tulips bloom, so there is more sun in the spring garden then one might suspect.
-- Soil conditions: Plant bulbs in a well-drained area. This is essential for naturalizing, since wet soil promotes fungus and diseases that can rot the bulbs.
-- Water: Water bulbs after planting. Water is essential in getting the plants to develop a strong root system before going into winter dormancy.
-- Nutrients: Fertilize with a low-nitrogen fertilizer at planting time and each fall after that. In spring, as the shoots break through the soil, use a high-nitrogen fertilizer.
-- Special care: Plant tulip bulbs in the fall about eight inches deep measuring from the base of the bulb. Include the mulch in this measurement.
-- Hints: After the bulbs have bloomed in the spring, cut off the flower heads but leave the green foliage to die back naturally. Always buy the biggest bulb available of the same variety, because the bigger the bulb, the bigger the flower. But bigger is not always better, since bulbs of a species tulip such as Tulipa tarda will be tiny beside a huge Darwin hybrid bulb.