Q&A: How to propogate your oak leaf hydrangeas

Q. I can propagate most any plant except oak leaf hydrangeas. Can you tell me how to do that?

- Frustrated in Portsmouth

A. Chesapeake horticulture agent Mike Andruczyk says oak leaf hydrangeas can be air layered or ground layered in February, March and April and then cut off and planted in the fall or next spring. He says cuttings in July with high rooting hormones (8 percent) and bottom heat will root.

Birds are drilling holes

Q. We have mysterious holes appearing on the trunks of many of our wax myrtles and flowering plum trees. What is it?

- Bonnie Seale, Chesapeake

A. The extension experts who examined the photo you sent suspect it is sapsucker damage. The yellow-bellied sapsucker is a bird that looks somewhat like a woodpecker. It goes around tree trunks, drilling holes from which it sucks out the sap. Go on the Internet and you can see what damage the bird can cause, killing tree limbs or the entire tree.

For prevention you can wrap the tree with hardware cloth. Some people apply Tanglefoot, a sticky substance available at garden centers or bird stores, but some animal lovers say the product can result in bird deaths.

Product for some weeds

Q. A product called Image can be applied over certain groundcovers to kill broadleaf weeds without damaging the groundcover. You recently had a question about what herbicide would kill wild strawberries in ivy. I personally have used it over Mondo grass and Vinca minor without damage. Always follow directions, which tell you to be patient, since it does not work overnight. This product was written up in Southern Living three years ago. We do stock Image at Anderson Home and Garden Showplace in Newport News.

- Dabney Morgan

A. Readers will remember Dabney Morgan from his many years at Coleman Nursery in Portsmouth. Dabney is a Virginia Tech graduate who has helped homeowners for many years.

I asked weed scientist Jeff Derr at the Hampton Roads Research Center to comment on Image, and he says, "Image can be used in liriope for broadleaf weed control. I do not promote the use of Image in landscape beds because of the risk of significant injury to azaleas, viburnums, abelia or bedding plants. Unless it is a bed that contains only liriope or other labeled ornamental species, I would not recommend it." The primary use of Image is for weed control in warm season turf such as Bermuda grass, he said.

Whiteflies more resistant

Q. I need some help before collard season gets here. The past two fall seasons, the whiteflies have taken over my collards. Last year, they ruined them completely. I tried everything I could think of to get rid of them but to no avail.

- G. Foster, Sr., Chesapeake

A. Whiteflies have become very resistant to most homeowner chemicals, says Chesapeake horticulture agent Mike Andruczyk.

He says to try Malathion, Permethrin, estenvalerate or Thiogard 3, applying three times four days apart. You'll get control, says Mike, if you use a different chemical each time you spray. You must cover the top and bottom leaf surfaces with the spray.

Or buy or make sticky yellow cards to capture the pests. Make them with yellow cards or poster board. Spread 90 weight gear oil or vegetable shortening on the yellow surfaces to trap whiteflies. Warning: small birds can also get caught on them. Also, buy resistant varieties of collard seeds.

Ask us

No gardening questions are taken over the phone. For a faster reply, e-mail rstiffler@dejazzd.com and include your city. Or, write to Robert Stiffler, The Virginian-Pilot, 150 W. Brambleton Ave., Norfolk, VA 23510. Fax to (757) 446-2963. Limit letters to one or two questions. For an earlier reply, send a self-addressed, stamped envelope.