It’s time to mow, plant and prune — then mow some more

It is a good week to plant geraniums, petunias and other annuals.

The third week of May is time for planting, pruning and more mowing. Spring has sprung so get out there and mow more often, prune back overgrown rhodies after they finish blooming, shear azaleas after they flower, thin branches and take out old wood from lilacs and other spring-blooming shrubs.

It is a good week to plant geraniums, petunias and other annuals as well as vegetables, trees, shrubs, vines, berries and anything else you find at the nursery.

Q. How often should I request that my gardener (that would be my hard-working husband) mow the lawn? I do not like the shaggy look, but he hates to mow. P.L., Puyallup

A. Once a week during the growing season is the general rule of green thumb but during the month of May and June most lawns do best if cut every four to five days. This is because grass blades do best with the top one-third of the blade is removed and in our Western Washington climate cool-season grasses thrive when allowed to grow to 3 inches tall between mowings and then shortening them by one inch. May is the month of maximum grass growth so lawns need mowing more often. Once summer heats up, the grass growth slows down and lawns require less mowing.

Q. How should I prune an overgrown lilac? I do not want to cut it to the ground because then I will not get blooms next year. This lilac is healthy but the flowers are too high for me to smell them or cut them as the bush has turned into a tree. H., email

A. You can use the one-third rule on lilacs, large rhododendrons and other shrubs that have grown taller than you prefer. The first year, prune one-third of the tallest trunks down to one to two feet tall. These shortened trunks will not flower next year. The second year, shorten or remove another third of the tallest branches and the third year shorten up the last of the old branches. By the third year the trunks you cut back first will be mature enough to flower so you won’t be without lilacs in the spring despite the radical renovation of your old lilac. Lilacs will also produce side shoots that can be removed from the mother plant and replanted as fresh new starts with lower growing blooms.

Q. You recommended a flowering vine called Black-Eyed Susan to climb up small trees and shrubs for summer color. Is this the same vine as Thunbergia? W.M., Kent

A. Yes, Thunbergia is the botanical or Latin name of the cheerful flowering vine that earned the common name or folk name Black-Eyed Susan to describe the dark black center eye in the middle of bright orange or yellow trumpet-shaped blooms. Given warm soil and a sunny spot this heavy bloomer will cover a wall, shrub or trellis with bright color until frost when winter kills the plant like it does all annuals. New colors of Thunbergia from Proven Winners means you can now find it in bright yellow, deep orange or a Tangerine and yellow combo color. Local nurseries may sell Thunbergia in four-inch pots to plant into the ground or in large containers already climbing a trellis or teepee. You can also grow Thunbergia from seed but this tropical plant needs warm soil to germinate so they do best started indoors in early spring and transplanted to warm soil in June.

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