Extension News

Ask the ISU Experts

Note to media editors: Got gardening questions? Contact the Hortline at (515) 294-3108 (Monday-Friday; 10 a.m. -  noon and 1 - 4:30 p.m.) 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 sprout an avocado seed? 

To sprout the seed, remove it from the center of the fruit and wash in water. For propagation purposes, the broad end of the seed is considered to be the bottom. The pointed end is the top. Insert three or four toothpicks into the sides of the seed. They should be placed about halfway up the seed. Then suspend the seed in a glass of water. The bottom one-fourth of the seed should rest in water. The seed should sprout within a few weeks.


During this time, periodically add water to maintain the initial water level. If the seed doesn’t sprout within 2 months, discard it and begin another. The roots are usually the first to emerge from the seed. The stem appears later. Pot the seedling when the root system has become well developed. The roots should be at least 2 to 3 inches long. 


Remove the toothpicks and plant into a 6- to 8-inch diameter pot using a commercial potting mix. Position the seed in the center of the pot. The top of the seed should be level with the soil surface. After potting, water thoroughly, then place the plant in a brightly lit location. A location near an east or west window is ideal. Water the plant regularly.  Keep the soil moist, but not wet. To encourage branching, pinch out the growing point when the avocado seedling is approximately 12 inches tall.  Fertilize once or twice a month during the spring and summer with a houseplant fertilizer. 


Are honeysuckles a good choice for the home landscape? 

For many years, Tatarian honeysuckle (Lonicera tatarica) and Amur honeysuckle (Lonicera maackii) have been widely planted in home landscapes, windbreaks and wildlife plantings. Native to Eurasia, these exotic honeysuckles are tough, durable shrubs.


Unfortunately, they can also be invasive. Numerous bird species eat the honeysuckle fruit (berries) and disseminate the seeds across the landscape. Seed-grown honeysuckles often appear in pastures, roadsides, woodlands and home landscapes.  In natural areas, these exotic honeysuckles may crowd out native species.


Because of their invasive nature, Tatarian and Amur honeysuckle are no longer recommended for landscape plantings in Iowa. Native or non-invasive shrubs are much better choices. Common buckthorn (Rhamnus cathartica) and glossy buckthorn (Rhamnus frangula) are other invasive shrubs that should be avoided when selecting plants for the home landscape. 


Are sweet cherries hardy in Iowa? 

Sweet cherries are not reliably hardy in northern and central Iowa. In these areas, sweet cherry trees usually die within a few years of planting. The low winter temperatures are simply too much for them to endure. 


Sweet cherries are most likely to survive and produce good crops in southern Iowa. The best varieties for gardeners in southern Iowa include ‘Gold,’ ‘Black Gold,’ ‘Hedelfingen,’ ‘Van,’ ‘Kristin’ and ‘Sam.’ Most sweet cherries are self-unfruitful. Plant two or more varieties for adequate cross-pollination and fruit set. 



Contacts :

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

Jean McGuire, Extension Communications and Marketing, (515) 294-7033, jmcguire@iastate.edu