Marianne Ophardt

Garden Tips: After 30 years, Garden Tips writer says goodbye ... part 1

Marianne Ophardt and a dahlia garden in 2002. After 30 years of advising Mid-Columbia gardeners with the perils and payoff of growing in this area, Ophardt is ending her popular column.
Marianne Ophardt and a dahlia garden in 2002. After 30 years of advising Mid-Columbia gardeners with the perils and payoff of growing in this area, Ophardt is ending her popular column. Herald file photo

After 30 years of writing this column every week and never missing a deadline once, I have decided to retire my pen at the end of this month. I have strived to provide you with interesting, science-based information that focused on gardening under the unique and challenging conditions encountered in our region.

Over the years, I have especially appreciated your readership and kind compliments. One of my favorites was, “I read your column every week, but I don’t usually follow your recommendations.” Believe it or not, it always made me smile and kept me humble. Another treasured comment from readers regarded the use of my column as proof that they were right in a gardening disagreement with their spouses. I hope it worked for them, because it almost never worked with my spouse!

My favorite column was the one I wrote comparing tree topping to chainsaw massacres. I think those of us who are passionate about healthy and beautiful trees have made headway in informing the public about the problems and dangers associated with topping trees. I won a national award for that column and have talked about the error of topping time and time again, but there is still work to be done. Please spread the word that topping is bad!

Along with tree topping, there have been other subjects that I have touched on more than once or twice. As I complete my tenure of as your garden columnist, I would like to repeat some of my often repeated sage advice.

WATER MORE DEEPLY, LESS FREQUENTLY: This is true for most lawns and gardens, except for those growing in sand, where more frequent watering may be necessary. However, the only way to tell for sure how often to water is to check the soil for moisture. Too many people set their irrigation timers in the spring and do not change them all season. Soil moisture should be monitored and irrigation timers reset when the weather changes from cool to hot and back to cool in early fall.

SELECT THE RIGHT TREE FOR THE RIGHT PLACE: I have written numerous columns on trees that should be avoided when selecting one for planting in your yard. Many longtime readers know that I am not a fan of sycamore trees. They grow to an enormous size that does not fit well in most home landscapes. Sycamores are also highly susceptible to sycamore blight, a disease that attacks them during cool, moist spring weather and frequently renders them devoid of leaves for the early part of the growing season.

Because they grow so big, sycamores are also a favorite candidate for tree topping, and I just told you how I feel about that! In the fall, giant sycamores drop a giant number of leaves and fuzzy seed balls. The best characteristic of a sycamore is its bark that gradually sloughs off in pieces, leaving an attractive mosaic pattern on the trunk.

Other trees that should not be planted in most local home landscapes include silver maple, weeping willow, box elder, cottonwood, and hybrid poplars. They grow very large and very fast. They tend to have invasive roots, weak wood, and are prone to wood rot. Trees that have serious pest problems that would be best to avoid include spruce, ash, and any birches that are not resistant to bronze birch borer.

You can find a lengthy list of trees suitable for our area, as well as a number of articles about trees that I have written on the Mid-Columbia Community Forestry Council’s webpage at

TIMING CRABGRASS PREVENTERS: One last time, crabgrass pre-emergent herbicide or “preventers” should be applied when soil temperatures are warm enough to allow for crabgrass seed germination. This typically occurs when the yellow-flowering forsythia has been in full bloom for several weeks, but can vary because of erratic weather. Your best bet is to use a soil thermometer and apply the material when the soil temperature at a depth of one inch is 55 degrees for at least a week. Plus, the best times to fertilize your lawn are early May, mid-June, early September, and early November, with the last two applications being the most important.

Next Week: Part 2 of the final Garden Tips

Marianne C. Ophardt is a retired horticulturist for Washington State University Benton County Extension.