Fluff up the old mulch instead of adding more: Ask the Ground Crew (2024)

Maureen Gilmer, SHNSMulching has many benefits, but keep depths at 1 to 2 inches around flowers.

By By Paul Pfeifer, Kent State University

I have a 10-year-old garden that has been mulched every year and composted every two to three years. While I have amazing soil, the depth seems to be overwhelming some plants as well as overflowing onto adjacent surfaces. Any suggestions? Replanting everything is not an appealing option because I have more than 450 varieties and can't even guess how many plants.

Also, when my ground reappears in the spring, I frequently have hosta roots exposed. I have been recovering them; is this necessary? -- Lori Roach

The benefits of mulching are retaining soil moisture, controlling weed growth, adding organic matter to the soil and maintaining gradual changes in soil temperature. Since your garden is mulched every year, you may be adding more than necessary.

For annuals and perennials, keep the mulch layer at 1 to 2 inches. Before adding new mulch, use a leaf rake to gently "fluff" the mulch and check the depth. If there are more than 2 inches, there is no need to add more.

Many homeowners find fresh mulch visually appealing. Mulch color can fade over time, but "fluffing" the existing mulch or adding a very thin layer of new mulch can provide that "fresh" look.

Hosta roots that are exposed to air can dry out, limiting their ability to take water from the soil. Also, bare roots can wick moisture out of the plant, causing the leaves to wilt quickly. Apply a thin layer of mulch over the unprotected roots of your hostas.

Roots growing at or above the soil level can indicate a need for division. Check the middle of the hosta clump, and if the center is noticeably devoid of leaves, divide your perennial in spring as the new leaves begin to emerge from the ground, or in early fall before the leaves start to go dormant. Autumn-divided hostas should be replanted by Oct. 1.

I have a 40-year-old grapefruit tree; it was started from a seed by my mom. I have kept it in a fairly large pot for the last 10 years. I have it outside during the summer and inside in the winter.

My problem is scale insects. For the past two years, it has been infested, and I've tried insecticidal soap on a regular basis, hand-washing each leaf and then coating with dormant oil. The insects are still very noticeable and cause sticky floors surrounding the pot. What can I do? I really don't want to throw it away; it has been my Christmas tree during some very trying times. -- Linda Eckenbrecht, Broadview Heights

There are several types of scale insects that suck sap from citrus trees, which can cause the leaves to turn yellow. If you see crusty or waxy brownish bumps on the stems or leaves, most likely your tree has brown soft scale. The sticky substance you are finding on the plant container and surrounding floor surfaces is the honeydew excrement of the scales (yuck!).

The best time to apply insecticidal soaps for brown soft scale is in the spring and again in midsummer when the crawlers are most active. You may also use imidacloprid, which is a systemic chemical pesticide that controls scale. Imidacloprid is normally applied to the soil of container plants and is absorbed by the roots and transported to the leaves and stems. It kills the scale as they feed on the plant.

Most garden centers carry pesticide products that contain imidacloprid. Always read the entire label before applying any chemical to a plant, and follow the directions exactly. Even though the scale insects are dead, they won't just disappear -- wipe the tree with a damp, soft cloth one more time to get rid of them completely.

Paul Pfeifer is managing director of Draime Estate Gardens of Kent State University, Warren.

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