Plant for Colorful Winter & Spring
Plant pansies and violas, as well as colorful mustards, cabbages and kales as soon as daytime temperatures stay consistently below 85 degrees F so these winter annuals have time to establish their roots before cold weather arrives. Then sow the seeds of poppies, larkspur and bachelor buttons in October or November, as they require several months of cool, damp conditions to germinate and grow in spring.
Mulch Trees with Moderation
Mulch is good for trees, especially those that are newly planted. It controls weeds, moderates soil temperature, and minimizes evaporation. However, mind the old adage, "everything in moderation." Large, volcano-like mounds invite decay and rodent damage to the trunk, and can keep the soil too wet, causing root rot.
Bring Vacationing Houseplants Inside
Bring houseplants inside in the next week or two, even if the days are still warm. The move will be less stressful now, rather than later when it is cool outside but heated indoors. There are a few exceptions to the rule, however. Plants that need decreasing sunlight and cool weather to bloom, such as Christmas and Thanksgiving cactus and some orchids, should stay out another month, unless threatened by an early frost.
Gamble on Delphiniums
If you're willing to take a risk, try growing delphiniums as super-hardy annuals by starting seeds now and transplanting them to a sunny part of the garden in December. Plant high in well-drained soil, water regularly, fertilize copiously, and if all goes well, they will bloom in late spring.
Prepare Roses for Winter
Stop fertilizing roses at least six weeks before the average first freeze to allow the new growth to harden off. Stop deadheading, too, so the hips (seedpods) will mature and encourage dormancy. Finally, clean away fallen rose foliage, which can harbor disease and insect pests over the winter.