Fungus, bugs and excellent pruning timing

Rot knot

Q: Are you able to determine this for me? [The reader sent photos.] It was on two small timber I minimize down.

A: Your black cherry tree had a case of black knot, a typical fungal illness. When a tree is contaminated, black galls type on the branches and generally on the trunk. A number of galls is not going to damage a tree, however over time the tree may have tons of of them, which might trigger contaminated branches to be deformed. Pruning out an contaminated department is one of the best methodology of management. Hardly ever are sprays advisable.

Hydrangeas’ variable blooms

Q: We now have some hydrangeas which might be 18 years previous on the north aspect of the home. One of many bushes produces full, spherical blooms, and the others appear like this. Is that this a variant of regular or is that this an issue? [The reader sent a photo.] The leaves appear unaffected.

A: Your hydrangea blooms are purported to appear like that. There are two flower varieties on huge leaf hydrangeas — the rounded ball-like blooms are known as mophead blooms, whereas the flatter blooms are known as lacecap blooms. The lacecap bloom has a middle of tiny, clustered flowers that look virtually like flower buds surrounded by a hoop of showy florets, which give it a lacy look, thus the identify lacecap. Completely different varieties may have several types of blooms.

When to prune butterfly bush

Q: I’ve a very giant, overgrown butterfly bush. It’s blooming so effectively however it’s taking over an excessive amount of area within the garden. I didn’t minimize it again this 12 months after I was purported to. If I minimize it again now, will I kill it?

A: You will not kill a butterfly bush or buddleia by pruning now, however you’ll scale back the variety of flowers it places on. You have got a couple of choices. You possibly can minimize it sparingly now or skinny it, chopping each different department again. When these branches rebound and start to bloom, minimize the opposite half out. Or minimize it again onerous, water effectively and look ahead to fall for extra flowers. The plant blooms on new progress, and as scorching and dry as it’s, rebound progress will not be fast. Subsequent 12 months, prune in late February.

Hibiscus-eating bugs stump reader

Q: One thing is consuming all my hibiscus leaves; I’ve a variety of them which were utterly stripped. I’ve tried a number of forms of bug spray and nothing appears to work. Are you able to inform me what insect is doing this and what is going to cease them? [The reader sent a photo.] I get pleasure from your column and have discovered it an awesome assist a number of instances. I actually will admire any make it easier to may give.

A: Your plant does have quite a lot of insect injury. From the looks, I might guess a mallow sawfly is guilty. The larvae of this insect appear like caterpillars, however when you look carefully, they’ve six or extra pairs of legs on the entrance of their physique. These bugs are extra carefully associated to wasps, however they do not sting. The grownup is a darkish, winged insect with an orange thorax (space behind the pinnacle). She is going to lay eggs on the hibiscus, and the rising larvae begin feeding. They will flip the leaves into lace over time. In Arkansas, they will have a number of generations per 12 months. Examine the vegetation and eliminate any larvae you see. Sprays of merchandise containing Spinosad will work, however use warning if there’s quite a lot of pollinator insect exercise on or across the plant.

Retired after 38 years with the College of Arkansas Cooperative Extension Service, Janet Carson ranks amongst Arkansas’ finest recognized horticulture consultants. Her weblog is at arkansasonline.com/planitjanet. Write to her at P.O. Field 2221, Little Rock, AR 72203 or electronic mail [email protected]

A number of black knot galls will not damage a black cherry tree, but when tons of type, branches turn out to be deformed. (Particular to the Democrat-Gazette)