 |
Dr. Gouin's Bay Gardener |
Salvation for Root-Bound Plants
End-of-season plants may be bargains but need help if they’re to survive
Many of the container-grown plants sold in late summer and early fall are root-bound. They have been grown in their containers all summer long, and now their roots have grown to circle along the inside walls of the container. It is for this reason that many garden centers offer these plants on sale; because unless they sell the plants, they will either have to be discarded or transplanted into larger pots before next year’s growing season. Plants that become root-bound deteriorate rapidly if left untreated.
To determine if the plant you are planning to purchase is root-bound, knock the plant from its container — by rapidly striking the top edge of the pot against a hard surface — and examine the roots. If you see mostly roots and very little rooting medium, the plant is indeed root-bound. If you purchase this plant and you want to ensure its survival, you should do the following.
- Place the plant in a pail of water and allow it to soak up water for at least one hour or until the root ball is saturated.
- Remove the plant from its container by either cutting away the container or inverting the plant and striking the top edge of the pot on a hard surface to dislodge the root ball from the container.
- Using a sharp knife, cut the outer layer of roots at three-inch intervals from the top of the root ball to the bottom. The cuts should penetrate the root ball by approximately one inch. Using your fingers, pull the roots from the bottom of the root ball toward the surface as much as possible to allow those roots to be planted close to the surface.
- Replant so that the surface of the root ball is visible at the surface of the soil after planting.
- Mix planting soil with a blend of existing soil and one-third by volume of compost, such as LeafGro, Chesapeake
Green or Chesapeake Blue.
Attack of the Plant Hoppers
Q Please help. We have an infestation of a white insect. I first noticed it on the hostas when they started to bloom. They like the stem of the flower when it is tender. It hops off the plant when moved, leaving a white area where it’s been. I know it’s not a spittle bug nor a white fly.
I tried Sevin, but it didn’t work. They are now on the raspberries, butterfly bush, new dogwood and all the new berry bushes that we planted. Please tell me what I can safely use that won’t hurt my berry bushes.
Thank you for your attention. I really enjoy your articles in Bay Weekly.
–Barbara Burton
A I believe you have plant hoppers, which carry a virus that will cause the leaves of your raspberries and dogwood trees to curl. Plant hoppers are a sucking insect, and you must use insecticidal soap and spray early in the morning. Spray at three- to four-day intervals for about five applications to get them under control.
From Scotland to Bay Weekly: The Yews of Crathes Castle
Q I have seen 300-year-old yews pruned to stumps (150mm thick and above) but with foliage on one side. The trees were planted in 1702 at Crathes Castle, Banchory, Scotland. Some 20 years ago, I was responsible for trimming the great yew hedges in a fine topiary style. You can see pictures of how the hedges looked at the National Trust for Scotland website.
I was shocked when I returned to the gardens this year to see that the yew hedges had been cut back to stumps. They are being given irrigation as well. Will they ever recover their former glory?
–Dave Paterson, United Kingdom, via e-mail
A There are very old yews in England, and I would have to refer you to the horticulturist at Kew gardens, where there are many beautiful old yews. All I can say is that it is difficult for very old plants to develop adventitious buds. However, I have seen 300- and 400-year-old redwood trees that were harvested in California develop sprouts from the stumps.
In the United States, yews were not imported until the mid to late 1800s. They were first planted in the Williamsburg area. I read about the history of the species for my master’s degree research on the nutrition of yews. The only native yew that exists in this country is Taxus Canadensis, and it does not grow this far south.
Professor Emeritus Francis Gouin retired from the University of Maryland, where he was the state’s extension specialist in ornamental horticulture. Follow his column of practical gardening and plant advice every week, only in Bay Weekly. Ask Dr. Gouin your questions at [email protected]. Please include your name and address.
