The Temecula Valley is experiencing a welcome moderation of temperatures, and gardens are showing improvement. However, cooler temperatures and more humid nights provide moisture to the vegetation which can create conditions for other problems, such as powdery mildew, white fungi on leaves upper surface, and black spot, dark splotches on leaves.
Roses benefit from a good rinsing to remove accumulated dust, but be sure to keep moisture off the blossoms to prevent yet another fungal disease, Botrytis, which will appear as rot of blossoms and will usually prevent them from opening.
Completing the light mid-season pruning in September or October as suggested in an earlier article pruned out dead and crossing canes and thinned the middle of the plant. This thinning will improve air circulation through the bush and reduce possible fungal diseases.
The mid-season pruning and fertilizing will encourage a new blooming cycle. Cutting some of the early blooms now and taking inside for bouquets can help ensure having blooms around Thanksgiving. Staggering the bloom cutting, might produce some blooms for your December holiday table even. That word might is the big unknown; the main factor begins with the temperature again. The average first frost date in this area is about Nov. 17.
Make a final application of fertilizer for the year before mid-November. It is recommended to use a fertilizer lower in nitrogen and higher in phosphate and potassium; that is, if your fertilizer has an N-P-K number on it, the first digit will be lower than the other two. If it lacks an N-P-K, read the ingredients or ask your professional nursery person for guidance. To explain, nitrogen encourages foliage growth which something we want to discourage as the plants go into their winter dormancy; phosphate helps build root structure and resistance to stressful conditions like the cold at this time of year; potassium is a helper of phosphate and aids in bloom quality. For an organic fertilizer, if applied now, it will be readily available when the soil warms and add to the nutrients needed for that spring growth spurt.
Don’t apply fertilizer after mid-November because it will only encourage tender growth that could be damaged by frost. Also, it will forestall the roses going into dormancy as the soil and general environment cool, daylight shortens, etc.
Some people think Southern California lacks distinct seasons, but we do have seasons. They are only discerned by those with a more sophisticated palette. So get out of the house and enjoy the subtle delights of the air, sun, and the rich aroma of our magically misty fall.
With a moment or two to spare, or feeling the need to get away, or when the day cools down, take a favorite healthy beverage, a picnic basket, and visit Rose Haven Heritage Garden, 30592 Jedediah Smith Road. The cross street is Cabrillo Avenue. The early morning and late afternoon sunlight across the pass is magical this time of year—it even makes the freeway seem a little bit romantic. Other venues are also lovely this time of year; check out the website http:pswdroses.org/calendat.html.
One last thing to do, when it gets just a bit too nippy out there, start perusing rose catalogs printed and online versions for that next “gotta have” rose variety. The Rose Society will be accepting entries in perfect bloom in the next rose show in April. Also, this time of year many nurseries and garden stores are liquidating their remaining inventory of potted roses, and November is an ideal time to purchase and plant roses.
For more ideas and information, visit www.TemeculaValleyRoseSociety.org.