The third week in May brings questions from gardeners about growing quandaries. Readers this week are puzzled by azaleas and peonies that just won’t bloom, problematic buttercup, where to apply mulch and how to get those tomatoes to ripen before fall. Here are easy answers to the most-asked questions this spring:
QWhy do some exbury azaleas go straight to leaf and forget to stop at the flower stage?
None of mine are in deep shade but some skip years and don’t bloom. K.K., Enumclaw
AMy best guess for a lack of blooms on azaleas is that the plants dried out just a bit in late August or September when they were setting buds. The driest time of year in Western Washington is in early fall and that is a crucial time for spring flowering shrubs. Rhodies, azaleas and camellias have very compact root systems and can be hand-watered during the dry season of late August and early September. This summer give them a good drink and see to it they don’t grow unhappy.
QWhy won’t my peony bloom? (asked by many people from many cities)
AMost likely it is planted too deep. Scrape away the mulch or soil so the union of the root with the stem is just barely beneath the soil. (I do love this question – removing mulch is such an easy answer.)
QDoes lime spread on the lawn stop the growth of buttercup? When should one spread lime? How much? A.N., email
ADolomite lime or calcium does not kill weeds or moss but it does slowly change our naturally acidic soil. Buttercup and moss love acid soil. Add lime every year to help break up clay soil, but keep it away from acid-loving plants like rhodies and azaleas. Apply lime in spring or fall when rain is abundant to wash it down to plant roots. Always read and follow the application directions on the package as there are different types and grades of lime. I prefer the pelletized lime often sold as “Soil Sweet” because the heavier particles are less likely to be blown away.
Q. Are there any plants that should not be mulched? I use Moo-Doo that is a dark mix of composted manure. L.P., Sumner
A. Don’t mulch plants from hot, dry countries such as Mediterranean herbs, lavenders, yuccas, sedums, thymes and cacti. Organic mulches such as bark dust, Moo-Doo and compost seal in moisture, help to block weeds and help improve soil structure but in our climate they also keep the soil cool and damp – and heat-loving plants hate this. Rocks and gravel are the preferred mulch for these unthirsty plants.
Q. What vegetables do well in the shade? T.P., Tacoma
A. Leafy edibles such as Swiss chard, lettuce, spinach, kale and some herbs like mint will survive in partial shade – but most vegetables crave full sun especially in our cool climate.
Q. Why do my tomatoes never ripen before fall arrives? Anon, email
A. In our climate you need to plant tomatoes in the hottest part of the garden and choose varieties that ripen quickly. The small, fruited tomatoes such as patio tomatoes, cherry tomatoes, Sweet 100, sweet One Million and Husky Gold all ripen quickly and are the most dependable in Western Washington.Marianne Binetti is the author of “Easy Answers for Great Gardens” and eight other gardening books. She has a degree in horticulture from Washington State University and will answer questions at her website binettigarden.com.