The Bay Gardener
By Dr. Frank Gouin
Garden Math: Dividing and Multiplying Hostas
The only way to conquer these monstrous perennials is to divide
If your hostas have become too large, now from mid August to late September is the time to dig and divide. Convince your friends and neighbors, who may have different cultivars of hostas, to do the same and organize a hosta swap. A well-publicized hosta swap will allow you to increase your collection of hostas at no additional cost.
Hostas have a rather limited root system despite their ability to tolerate drought. Using a shovel, lift the hostas out of the ground by first forcing the shovel straight into the ground, starting approximately six inches away from the edge of the crown. Before lifting the plant, cut the soil deep, at least the length of the shovel, around the plant before lifting. The soil should be moist but not wet.
After lifting the plant from the hole, slam the root ball on the ground to shake the soil from the roots. You may have to slam the plant several times before the entanglement of roots at the base of the crown become visible. If your soil is clay or heavy silt, you may need a strong stream of water to wash away the soil.
Using a sharp knife or a hatchet and a hammer and starting from the outer edge, separate the small crowns, which will consist of two to five stems. Place the blade of the hatchet between two small crowns and hit the head of the hatchet with a hammer. Each small crown should have roots attached. To get large plants sooner, I generally allow two to three small crowns to remain together as a single division.
To keep the roots moist during the dividing process, as soon as you divide each crown or clump of crowns, place the roots in a pail of water. To gain a rapid start with your new divisions, amend the destination soil with compost and limestone. Spread an inch-thick layer of compost and apply two cups of dolomitic limestone per 100 square feet of bed area, spading them in before you plant. Hostas will grow in soils of a wide pH range, but an abundance of organic matter and calcium gives tiny roots a healthy, fast start.
How to Use Chemicals Selectively
Q You wrote that the only way to rid a lawn of Bermuda grass is killing the whole lawn with Roundup [Vol. xiv, no. 32: Aug. 10].
My lawn runs right up to a bed with azaleas, magnolia, fringe tree and epidium. I’m worried about over-spray. Could I apply the Roundup with a sponge or mop and get the same kill effect on the Bermuda but not kill my other plantings?
Doug Smith, Annapolis
A You can use a sponge mop, but you will need to mix the Roundup at a concentration of one part Roundup to seven parts water. This means that you must purchase the concentrated Roundup and not the diluted ready-to-use spray.
In the lawn area you can spray the Roundup on a calm day without drift problems. With situations like that I use a wick applicator, starting from 12 inches, from the garden area, with low pressure.
With a wick applicator, you can actually treat weeds under the branches of plants without affecting them. On the web go to www.hummert.com and order the walk a wick weed wiper.
Ask Dr. Gouin your questions at [email protected]. All questions will appear in Bay Weekly. Please include your name and address.