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Magnolia blossoms

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Got gardening questions? Contact the Hortline at (515) 294-3108 (M-F; 10-12 & 1-4:30) or send an e-mail to hortline@iastate.edu. For more gardening information visit us at Yard and Garden Online at www.yardandgarden.extension.iastate.edu





How do you force branches of spring-flowering trees and shrubs indoors? 


Forcing can be done as soon as the buds begin to swell.  This may be as early as February for forsythia or pussywillow. It’s best to wait until early March for more difficult-to-force ornamentals, such crabapples, magnolias and redbuds. Select branches containing many round, plump buds. Narrow, pointed buds are usually leaf buds.  Flower buds are generally larger and have a more rounded shape than do leaf buds. 


Make clean, slanting cuts 1 to 2 feet from the tips of the branches with a sharp hand shears or knife. Selectively remove branches that won’t harm the natural shape of the plant. If possible, collect the branches when the temperature is above 32 degrees F. If the plant material is frozen when collected, submerge the branches in a tub or pail of water for a few hours.


Later, set the branches in a tall container of water and place in a dimly lit, cool location. Spray or mist the branches several times a day to prevent the buds from drying out. Change the water in the container daily during the forcing period. Daily changes of water should inhibit the growth of bacteria and fungi that could interfere with the absorption of water by the branches. When the flower buds begin to open, move the branches into a bright room. Keep the flowering branches out of direct sunlight and in a cool location to prolong the bloom period. 


The time required to force branches into bloom depends upon the plant species and collection date. Forsythia and pussywillow generally take only one to three weeks to force. Magnolia branches may take three to five weeks. The closer it is to their normal outdoor flowering period, the less time it will take to force the cut branches indoors. 


I would like to plant an apple tree this spring.  Do I need a second tree for pollination? 


Pollination and fertilization are necessary for fruit development. Pollination is the transfer of pollen from the anther to the stigma. Fertilization is the union of the male sperm nucleus from the pollen grain and the female egg found in the ovary. 


Self-fruitful trees bear fruit when pollen is transferred from the anther to the stigma on the same flower, another flower on the same tree, or within a variety. Many fruit trees, however, cannot produce fruit from their own pollen. These trees require pollen from another variety and are called self-unfruitful. 


Apples are self-unfruitful. Plant at least two different apple tree varieties within 50 feet of one another for good fruit set. Some apple varieties, such as Golden Delicious, will produce a crop without cross-pollination from a second variety. However, best fruit production occurs when two or more apple tree varieties are planted in the same general area. 


Is it possible to save tulip bulbs that have been forced indoors? 


Tulips, hyacinths and most other spring-flowering bulbs that have been forced indoors are usually discarded after flowering.  Most won’t flower again when planted outdoors and attempts to force them again are usually unsuccessful. Daffodils are an exception. Many forced daffodils will bloom for several years when planted outdoors. 


The care after flowering is important if attempting to save forced bulbs. After blooming, remove the spent flowers and place the plants in a sunny window. Water regularly until the foliage begins to yellow. At this point, gradually cut back on watering until the foliage withers and dies.  Carefully remove the bulbs from the potting soil, allow them to dry for one or two weeks, then store the bulbs in a cool, dry location until fall planting. 




Contacts :

Richard Jauron, Horticulture, (515) 294-1871, rjauron@iastate.edu

Jean McGuire, Continuing Education and Communication Services, (515) 294-7033, jmcguire@iastate.edu

There is one photo available for this week's column.

Magnolia blossoms, (MagnoliaXCU1-18-06), 460 KB