December 7, 2013

1 - Rose seeds may be grown into new plants if the required conditions are met.

Yard and Garden December 7, 2013

Q.

My roses produced many beautiful flowers and a lot of fruit with seeds in them. Can I plant these seeds? Do I need to do anything special to them to make them grow? Is it worth doing?

A.

While it is usually recommended that gardeners remove the flowers as they fade to prevent fruit formation, unless the gardeners want the rose fruit (rose hips) for jelly or tea, you can plant the seeds and probably have many of the seeds sprout. Whether or not it is worth it depends on why you are trying to grow roses from seeds and which roses you are growing.

Wild roses and species roses (cultivated roses that are genetically identical to their wild ancestors) will produce offspring from seed that look much like the parent plants. Seed from hybrid roses will produce plants that may look quite different from the parent plants. That is because the hybrid roses contain genetic contributions from diverse sources. Almost any characteristic from their diverse ancestry may appear in the offspring. These may be positive characteristics, or negative characteristics. Perhaps a new and beautiful combination of characteristics will be produced. However, this outcome does not have a high probability.

If your purpose is to grow roses that look like the parents, planting the seeds is worthwhile only if the plants are from the wild or species plants. If your purpose is to grow new plants out of curiosity or an attempt to grow new plants with exciting new combinations of genetic characteristics, seeds from the hybrid roses may provide you some interesting results. The chances that any offspring will be superior to the parent plants may be minimal, but the fun of trying to grow something new may make it worth it to you.

Because most roses are from temperate climates with distinct, cold winters and their fruit and seeds are produced in the late summer and fall, the seeds much have a mechanism to prevent them from beginning growth until winter has ended. This mechanism is dormancy. The seeds must experience a period of cold temperatures before they will germinate. The seeds must be kept moist and cool (not frozen) for 4 to 6 weeks. Temperatures between freezing and 40 degrees are best. Temperatures above 50 degrees will delay the overcoming of dormancy. You should put the seeds in a resealable plastic bag with moist peat moss, potting soil, or rolled in paper towels. Then put these bags in a refrigerator (not freezer) for the 4 to 6 weeks. They may be refrigerated longer, but watch for signs of sprouting. If the seeds begin to sprout, or at the end of the treatment time, the seeds may be planted in pots with good potting soil and placed in a warm environment to germinate. They may also be planted in the garden to germinate when outdoor temperatures become warm enough to allow growth.

It may take several years for the plants to reach sufficient size to begin producing flowers. When they begin flowering you will finally know if you have plants worth keeping or not. This can be fun, but may result in few desirable plants. However, there is a chance that a new, superior variety may be produced.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

Links:

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook page.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!