Gardening tips and suggestions.
Many of the daisy-like flowers such as Rudbeckia, Helenium, Symphyotrichum, and Chrysanthemum will form a mass of flowers that will eventually topple over the edge of the beds. While a cascade of color can be attractive spilling over the edge, it looks very unsightly when you expose the brown bare centers of the plants. It is best to stake these plants as a group or clump.
Tall perennials with large flowers like Lilium, Delphinium, Crocosmia, and Dahlia will benefit from individual stakes.
Feeling stressed? Recent research shows that visiting a botanical garden or arboretum can help you cope and make you feel less stressed, at least temporarily. Go see the foliar beauty at the Washington Park Arboretum,the Bellevue Botanical Garden or your local public garden and start coping with your stress!
Tammy Kohlleppel, Jennifer Campbell Bradley, Steve Jacob. “A walk through the garden: Can a visit to a botanic garden reduce stress?” HortTechnology 12(3), July-September 2002, 489-491.
A common question gardeners have is when to prune. “When the shears are sharp!” is the often-heard answer. In reality there are a few timing guidelines that do matter.
First of all, certain trees are known to “bleed” when pruned while the sap is rising in late winter and early spring. Maples, dogwoods, birch, elm, walnut and honey locust are the most common.
Bleeding usually won’t hurt the tree, but the pruning cuts are slower to heal which may leave susceptible trees vulnerable to infection. These trees should be pruned right after leaves fall off in autumn.
Cherry trees are at risk from the destructive cherry bark tortrix. The tortrix is attracted to fresh pruning cuts, so cherry trees should not be pruned between May and August when the tortrix is active.
Spring flowering shrubs should be pruned immediately after flowering so that the new growth has time to form next year’s flower buds. Summer flowering shrubs may be pruned in winter because flowers are formed on this season’s growth.
Pruning resources online:
Research from Purdue and Cornell University shows that autumn leaves can simply be left where they fall, shredded by a mower and allowed to mulch the lawn. Fertilize as you normally would. The shredding is essential, so don’t skip that step. If the leaf mulch is too thick, move some into your flowerbeds or compost bin. Read the research report.
Yellowjackets are at their most aggressive in late summer so it is understandable that people want to destroy their nests. Before you pull out the can of pesticide, remember that wasps are considered beneficial insects that eat plant-eating bugs, and will only inhabit their nest for one season. This article from University of Minnesota Extension gives good advice on how to deal with these insects.
By November Seattle has usually had a good hard frost and most of our herbaceous (non-woody) perennials have either turned to mush or look a bit tattered. Before you give in to the temptation to cut back everything in sight, consider the advice of natural gardening advocates James Van Sweden, author of Gardening with Nature (Random House, 1997) and Jackie Bennett, author of The Wildlife Garden (David & Charles, 1993):
On the other hand, sanitation is critical if your apples suffered from codling moth or scab or your roses suffered from black spot. Rake up and dispose of every single diseased leaf or infected fruit. Insect and disease organisms also over-winter on plant debris, so if you had a problem this year, start the treatment now with a thorough clean-up.
Spring is the time to prune Group 3 clematis back to 1 foot tall. These clematis bloom in late summer/fall. Read the why and how of pruning other groups of clematis on the web at the Royal Horticultural Society website.
Leave it to gardeners to transform innocent seeming Bambi into a plant eating, garden destroying monster! Outwitting Deer by Bill Adler Jr. (Lyons Press, 1999)uses humor to reveal the truth about the largest pest in the garden. The long lists of plants that deer prefer and dislike (no plant is 100% deer-proof) are most helpful, along with an honest examination of the myriad of strategies and home remedies used to repel marauding deer.
Weed fact sheets are available from UC Davis, in cooperation with the Nature Conservancy. This is an excellent resource for learning how to control some of the most tenacious invasive plants in the US. Many weed profiles have color pictures, “success stories,” and references to research.
Hostas are shade loving foliage plants that thrive in our moist temperate climate. The American Hosta Society is devoted to promoting the genus and introducing new cultivars. Visit their website to read about the most popular hostas and how to grow them to perfection. Membership costs $25.00 per year and includes a fabulous color journal three times a year.