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The Science of Spring-Flowering Bulbs

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The Science of Spring-Flowering Bulbs THE SCIENCE OF SPRING-FLOWERING BULBS Inside the tulip bulb Flower bud In the center of Scales the bulb is a baby Thick, fleshy flower bud. leaves are arranged Tunic TULIPTIME around the Paper outer stem covering Not every spring flower is created the same way. The stages of growth Learn about the root causes of our gorgeous gardens 1. Planting 2. Making 3. Cooling 4. Growing 5. Blooming 6. Time to 7. Multiplying By Christine Facciolo time roots period period time regenerate bulbs Special to The News Journal April - May May - June July - Sept. Basal stem Sept. - Oct. November Dec. - Jan. Feb. - March othing announces the arrival of fleshy scales from drying out. Imbricate bulbs like the As the tulips bloom After the bloom- Up to five small bulbs The compressed stem con- Roots The tulip bulbs are The roots start Now starts the rest The bulbs begin to spring better than a flower garden lily do not have this protective covering and must be they receive ing period, the can be expected to nects the flower, scales Grow out of the planted. Most growing out of the period. In order for change as the full of colorful and fragrant kept moist prior to planting. basal stem their nourish- flowers are cut grow out of the and roots of the plant important: plant base. They establish the bulbs to bloom starch, or carbohy- blooms. The plants that grace Like the bulb, a seed is a miniature plant with a ment from and the leaves are mother bulb. They these gardens come from either protective cover and a food supply called endosperm. them twice as deep themselves in the in the spring, they drates, in them the roots left on the plant. form their roots slow- seeds or bulbs. So if seeds and But unlike the bulb, the seed shows none of the struc- as the bulb is high. dirt and take nour- need weeks of at turns to sugar. As only. The The new daughter ly and develop their bulbs both produce plants, what tures found on the adult plant. Indeed, the primary They have no roots ishment out of the least 40-degree this occurs, the Fun facts skin of the bulbs will be using blooms and leaves exactly is the difference between purpose of the seed is to germinate a plant formed at this stage. dirt. The mother temperatures. Frost leaves and flower bulb barely the food values of the two? from the genetic material of two parent plants. • Currently, there are about 75 wild within the bulb, for All plants—even bulb plants— Seed plants can be annuals, biennials or perenni- bulbs get ready for at this time does gradually push up- the leaves to species of tulips and 150 species in remains as all of next years plant. Noriginate from seeds. The major difference between als. Bulb plants, on the other hand, are equipped to sur- winter. not harm the bulbs. wards out of the the energy goes grow. total, with more than 3,000 varieties. bulb. bulbs and seeds lies in the role each plays in the life vive over the long term. Bulb plants are naturally to the bloom. cycle of the plant and their function. Seeds develop perennial and, with proper care, will grow annually for • The word tulip is derived from a after sexual reproduction combines genetic material many years. Persian word called delband, which from parent plants. Bulbs, on the other hand, develop Bulbs are divided into two categories based on when means turban. from asexual or vegetative reproduction when plant they bloom. Summer-flowering bulbs such as the lily cells divide and form a copy of the parent plant. These are too tender to survive harsh winter conditions and • Tulips are native to the mountainous new bulbs are called offsets or bulbets. are planted in the spring. Spring-flowering bulbs like areas of Central Asia and have been “When you plant a bulb, you’re sure you’re going the tulip are often called hardy bulbs because they can cultivated for more than 500 years. The to get the kind of plant you like,” said Rose Ogutu, survive in cold temperatures. In fact, they need the tulip is the national flower of Turkey Ph.D., horticulture specialist for Delaware State Uni- cold in order to flower properly. and Afghanistan. versity’s Cooperative Extension. “If you plant them in October or November and 40° A bulb is a plant that grows from an underground they get that cold treatment, you should have a show in • The mass of food storage tissues. The primary function of the spring,” said Carrie Murphy, ornamental horticul- Netherlands these underground storage structures is to provide the turist with the New Castle County Cooperative Exten- remains the plant with enough nutrients to ensure the plants sur- sion at the University of Delaware. vival when it’s resting or waiting to be planted, said Some other plants that we call bulbs are not true world’s main Martha Stevens, public landscapes manager at the bulbs because they lack one or more characteristics of producer of Delaware Center for Horticulture. the true bulb. Corms like the crocus and gladiolus commercially Botanically speaking, a bulb is a modified store food in a large basal plate but have no sold tulips, pro- stem containing a miniature plant sur- fleshy scales. Tubers such as dahlias ducing as many rounded by fleshy scales, which provide lack a basal plate and do not pro- as 3 billion food and a basal plate, which pro- duce offsets. Rhizomes such as Bulb duces roots. iris, calla lilies and cannas, bulbs annually, Tunicate bulbs, like tulips, differ from other storage mostly for daffodils, hyacinths and orna- structures in that they grow export. mental alliums, have a paper- horizontally along the sur- like covering called a tunic face of the soil or just • Tulips came that protects the under it. to Europe in the 16th century via a gift from the Ottoman Empire. They were introduced to the United States in the 1800s. • Tulips require a period of cold dormancy called ver- Tulipmania Design and graphics by nalization to flower. The Dutch obsession with the tulip led to Dan Garrow/The News Journal a period from 1634-1637 known as Tulipma- • Tulips normally have nia. Tulipmania was the world’s first major one flower per stem but financial bubble. Investors began speculat- a few species have up ing in tulips, driving prices to unprecedented Where to to four flowers on a sin- highs. The average price of a single flower gle stem. exceeded the annual income of a skilled see tulips worker. Tulips sold for 4,000 florins, the currency of the Netherlands at the time. • Lewes Tulip Festival When prices fell dramatically over the Lewes, Thursday, April 10 - course of a week, many investors April 12, (302) 645-8073 went bankrupt and the • The Inn at Montchanin economy crashed. 514 Montchanin Road, Montchanin, SOURCE: Investopedia.com (302) 888-2133 (garden of tulips near the “Pink House”) • Loockerman Street Dover (tulips blossom in the grassy median near Post Office) • Longwood Gardens 1001 Longwood Road, Kennett Square, Pa. (610) 388-1000 • Mt. Cuba Center 3120 Barley Mill Road, Hockessin, (302) 234-4244, www.mtcubacenter.org • Valley Garden Park Campbell Road, Greenville, (302) 576-3810 ONLINE QUIZ AND SOURCE: INTERACTIVE GRAPHIC Test how much you’ve learned about THE SCIENCE OF TULIP BULBS at delawareonline.com/didyouknow COMING NEXT WEEK: DOWNTON ABBEY STYLES.
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