fb pixel

Log In

Reset Password

Fall is a good time to plant certain perennials

With the promise of cooler weather coming our way, which perennials are best to plant now instead of spring.

As you choose perennials, remember that in the Rogue Valley, not only is winter cold tolerance a consideration, but summer heat must be taken into account. That factor was well demonstrated this past year, wasn't it?

There are three gardening zones used in southwestern Oregon. The old standby is the United States Department of Agriculture Plant Hardiness Zone. But the Sunset (named for its popular and dependable magazine) Western Plant Climate Zone, and the American Horticulture Society (AHS) Heat-Zones are also frequently used in reference books, plant tags and nursery catalogs.

While all three of these references are useful, it's helpful to know that the Sunset zones are based on a combination of extremes of heat, rainfall, temperatures and humidity, while the AHS's heat zones were developed to provide a measurement of summer heat stress on plants. The USDA zones are more general. You will find Zones 6 to 8 mentioned most frequently by all three, for our area.

By now, your head may be spinning, as you realize that there are no hard-and-fast rules to follow, as your yard will also be affected by altitude and air drainage. So, how can we simplify things a bit?

Although rules-of-thumb can serve as guidelines, common sense needs to be part of the mix, too. So here are a couple of guidelines for you. In the fall, plant or transplant shrubs that bloom in the spring and like it a bit cool, such as azaleas, rhodies, Japanese maple, roses and dogwood. Planting in the fall gives them enough time to develop roots over the winter, so that they are ready to bloom in the spring.

Heat-lovers such as olive, escallonia and oleander can be planted or transplanted in the spring. But keep in mind that just because these and other heat-lovers will survive the summer, this is no guarantee that these plants, and others of the same ilk, will make it through the winter. If you decide to plant them, they may need extra protection during cold weather.

Space does not permit me to describe how to plant these perennials, so be sure to talk to your nurseryman about that. "Garden Guide for the Rogue Valley – Ornamental Trees and Shrubs" is packed with good information, as it was written by local Master Gardeners for local conditions. You can buy it at most local nurseries, or from the OSU Extension Service.

Coming Up: Master Gardeners Marjorie Neal, Marsha Wait, and Jody Willis will discuss dividing rhizomes, crown root perennials and day lilies from 7 to 9 p.m., on Thursday, Oct. 2. Cost is $10, and the class will be held at the Southern Oregon Research and Extension Center, 569 Hanley Road, Central Point. Call 541-776-7371 to register.

Circle Nov. 1 on your calendar to attend the Master Gardeners' Winter Dreams, Summer Gardens symposium. This all-day gathering of gardeners offers 40 classes from which to choose four. Topics cover all aspects of gardening. Call 541-776-7371 for an information packet.

Carol Oneal is a past president of the OSU Jackson County Master Gardeners Association. Email her at diggit1225@gmail.com.