Hollies need to be blooming together for fertilization

Backyard Q&A

In The Garden

December 28, 2003|By Dennis Bishop | Dennis Bishop,Special to the Sun

This spring, I planted three female hollies and one male holly in my back yard. I expected they would pollinate one another and produce fruits, but I got none. What may have happened?

There are several reasons why your plants may not have produced fruits. I am not sure what type of holly you planted, but the male and female plants must be compatible for fruiting to occur. In most cases, a male plant will fertilize a female plant within the same species.

However, with so many new cultivars on the market, there is a lot of variability in flowering time. Some plants flower early and others flower late. If the male flowers are not open and producing pollen at the same time that the female flowers are open and fertile, fertilization will not take place, and no fruit will be produced. I suggest that you call the nursery where you purchased your plants and ask if they are compatible. If they are not, exchange the male plant for a different cultivar.

A second reason your plants may not have produced fruits is improper location. Your hollies may very well have bloomed before you brought them home from the nursery. Even though your male and female plants may be compatible, if they were grown in different greenhouses or were otherwise separated at the nursery, it is unlikely that fertilization took place. Now that all the plants are in your back yard, they should fertilize one another next spring and produce fruits for you next fall.

Several weeks ago, you suggested soil preparation and planting tips for boxwood, but you did not recommend disease-resistant varieties. Why not?

Most of the boxwoods being sold in nurseries are from one of two species, Buxus sempervirens (common boxwood) or Buxus microphylla (little leaf boxwood). In addition, a number of new cultivars and hybrid plants have been developed from the two species. While some are reputed to be resistant to some boxwood diseases, I am not aware of any boxwood resistant to phytophthora root rot. I have seen very large plantings of the new cultivars and hybrid plants being decimated by disease in poorly drained soil. I would not recommend planting any boxwood without preparing the soil well.

Dennis Bishop is an urban horticulture educator for the Baltimore office of the Maryland Cooperative Extension Services. If you have a gardening or pest problem, you can call the Home and Garden Information Center hot line (Monday through Friday, 8 a.m. to 1 p.m.) at 800-342-2507. You can also e-mail questions, order publications and diagnose plant problems by visiting the Web site www.hgic. umd.edu.

Checklist

1. Allow potting soil to dry out before watering your houseplants. Over-watering is a major cause of houseplant problems during the winter months. With the shortening of days, houseplants slow their growth during the winter months. Fertilization can therefore be reduced to once a month until strong growth resumes in spring.

2. Avoid using chemical fertilizers containing nitrogen and phosphorous to melt ice around your home. Call the Home and Garden Information Center (800-342-2507) for information on recommended ice- melting materials.

Baltimore Sun Articles
|
|
|
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.