To do this week
* Harvest tomatoes that have split and use them immediately. Split tomatoes left on plants will attract sap beetles and are also prone to invasion by decay-causing fungi. Splitting of tomatoes is most often caused by uneven watering. Certain varieties, e.g. the very popular ‘Sweet 100’ and other cherry tomatoes, are more prone to splitting than others. To prevent splitting, water tomato plants deeply every 2 or 3 days, taking rainfall into consideration.
* Continue to check for insect pests in the vegetable garden. Cucumber beetles, cabbage worms, tomato hornworms, corn borers and bean beetles are busy sampling the fruits of our labor. Select low impact or “biorational” pesticides as opposed to synthetic chemical pesticides when shopping for pest control materials.
* Prune raspberries after summer harvest is completed. Cut out the old fruiting canes back to ground level. Removing the old canes will help reduce the spread of cane blights while opening up the planting and allowing for more light to reach this year’s new growth. This in turn will promote better fruit bud development.
* Cut some leafy shoots from purple leaf varieties of shrubs, e.g. smokebush, weigela, and sand cherry, to complement the colorful blossoms in floral arrangements.
* Take cuttings from the tips of stems of bell flower, crane’s bill, flax, Jacob’s ladder, Marguerite and Shasta daisy, and penstemon. Root the cuttings in a moist mixture of sand and perlite.
* Dig and divide irises, including bearded iris and Siberian iris. Usually, bearded iris needs to be divided about every 3 to 5 years, while the faster growing Siberian iris may need to be divided more often, i.e. at 2- or 3-year intervals, in order to maintain maximum bloom.
The most frequent question I get lately is “Can I transplant perennials and shrubs now?” The answer is an unequivocal “It depends.” (I’ve really mastered the skill of the cagey response. I should be in politics.)
With slightly more than a month to go before fall arrives, this is a good time to transplant certain plants. “Transplanting” refers not only to digging and moving plants now in the ground but also to planting container grown and balled and burlapped plants available at retail nurseries and garden centers. Generally speaking…uh, writing, plants which are hardy to this region can be transplanted in late summer and early fall. On the other hand, plants that are borderline hardy are best planted or transplanted in early spring. So, check the hardiness rating of plants intended for transplanting.