The Bay Gardener
By Dr. Frank Gouin
Garden Math: To Multiply Peonies Divide Now for More Blooms
Big plants make small flowers
August and September are the time to dig and transplant peonies for flash, full flowers next May.
You know your peonies need dividing when the plants are getting too big for their space. At the same time, the flowers are likely to be getting smaller.
Peonies’ fleshy, tuberous roots looking like little sweet potatoes are fragile. Damage during digging opens the door to root-rotting organisms that can be lethal for peonies.
Regardless of the type of soil, peony roots tend to be shallow, just below the surface. When digging these plants, start along the drip line of the foliage. Lift the tuberous roots out with a digging spade, then remove all soil from the tuberous roots for close examination. If the roots have been damaged, use a sharp knife to make a clean cut so as to promote rapid healing. To prevent root rot, dip the cut surface in Captan dust. Or lay the cut roots in a warm shaded area either overnight or for a half day to allow the suberin (a sugar-like substance in the root) to form a thin callus over the cut surface. The dried suberin inhibits root rot.
Peonies grow best when planted in well-drained, rich, organic soil, amended with lots of compost; the more the better. When transplanting peonies, plant the bud or eye at the stem end of the tuberous root less than one inch below the soil’s surface. Plant the tuberous roots too deep, and they will not flower. I plant mine so that the tip of the bud is at the surface of the soil, then mulch it with enough compost to hide the bud.
Questions from Shoppers at the Deale Farmers’ Market
Q I took your advice and planted purple Gita beans [Vol. xiv, No. 22: June 1]. But they’ve stopped producing. What’s wrong?
A Remember to pick your Gita beans when they’re 12 to 14 inches, before the seeds form in the pods. This means picking every day, or at least three times a week. Once the pods produce seeds, the plants stop producing.
You’ll remember that my beans seemed washed out by heavy rains [Vol. xiv, No. 33: August 17]. Now the soil has dried, and they’ve come back with a fury. Now I’ve got plenty of beans; I’m picking three times a week.
Q You told us to pick bagworms off our trees early, then throw them on the ground to encourage natural predators to help us do the work [Vol. xiv, No. 29: July 20]. I did, and now they’ve crawled back up and reattached themselves.
A Don’t worry. That’s as far as they can get. They’ve worn themselves out dragging the bag and reattaching, so they won’t survive the winter to reproduce.
Ask Dr. Gouin your questions at firstname.lastname@example.org. All questions will appear in Bay Weekly. Please include your name and address.