Q. I got some lily-of-the-valley plants from a co-worker to fill in around my hosta. I'm reading online that they can be invasive. Any advice? -- Kelly Turner Davis, Paulding County

A. Growing in perfect conditions lily-of-the-valley could be "pushy," but I don't think you'll have a problem. Invasiveness is typically a problem in the North. The white, fragrant flowers are beautiful in spring. Lily-of-the-valley prefers a cool, moist, shaded area. It does not like sunny spots that are hot or dry.

Q. I have heard you speak about "co-dominant" trunks, emphasizing that multiple trunks are not conducive to a tree's health. My ‘Bloodgood' Japanese maples have co-dominant trunks. Do I prune them? -- Bernie Schultz, email

A. Having two parallel trunks can be a problem for trees taller than 20 feet but your ‘Bloodgood’ maple won't grow that big. Remove twiggy branches from the top anytime to improve air flow and branch structure. I don't think pruning out multiple trunks would make the tree look better or live longer.

Q. I recently returned from Kansas and brought back some cotton burr compost. I've read this is excellent for gardens, although it's very stinky. Why can't I find it in the Atlanta area? -- Shelli Merrion, Roswell

A. University of Georgia cotton expert Guy Collins said cotton burr is basically gin trash: broken seeds, leaves, stems, etc. that are a byproduct of pulling cotton fiber off the seeds. Composting it is a good use for material that was formerly thrown away. Your compost has an analysis of 1-0-1 and plenty of soil-softening organic matter. I've not seen it for sale locally because we have few gins nearby. Local gardeners use cotton seed meal (6-0-1) as fertilizer and composted wood fiber for soil amendment instead.

Q. I have Boston ferns on my front porch every summer. In the middle of the summer I get fern caterpillars. Do you have any suggestions to prevent them? -- Rhonda Stephens, email

A. These caterpillars come from eggs laid on the fern by a moth while the fern was being grown in Florida. The eggs are difficult to spot but the caterpillars can quickly strip the foliage off a Boston fern. Get relief by spraying each fern, when purchased and in mid-June, with a product that contains Bacillus thuringiensis (B.t.). This product is specific for caterpillar control and is considered very safe.

Q. My rhubarb plants have suddenly produced a tall shoot with a flower on the top. Does this mean I can no longer eat the stalks? -- Bill Thomas, Marietta

A. You’re lucky to have rhubarb to consider eating. This perennial vegetable struggles to survive in our hot, humid conditions. The leaf stems are certainly edible, blooming or not, in contrast with the leaves, which are poisonous. To help your rhubarb conserve its energy, cut off flower stems as they appear.

Listen to Walter Reeves Saturday mornings on AM 750 and now 95.5 FM News-Talk WSB. Visit his website, www.walterreeves.com, or join his Facebook fan page at xrl.us/wrfacebook for more garden tips.