Bark damage on Japanese plum

The bark appears to be coming off around the base of our Japanese Plum trees. The bark appears to be normal on the rest of the tree. Does it have a disease or pests?

The loss of bark at the base of the Japanese plum could be due to insects or physical damage. A likely cause of injury is the bumping of the tree by a lawn mower or injury from a string trimmer used to cut weeds around the base of the tree. Could these be the culprit? Such damage might be one or more years old. Are there rabbits in the area that could be chewing the bark, perhaps field mice or voles? Has a dog been tied to the base of the tree? If you can rule out physical injury, then perhaps an insect is the problem.

A very common cause of bark damage at the base of plum trees is due to the peach tree borer which attacks all stone fruits, including plums. Is there jelly-like sap and/or sawdust like material at the base of the tree, perhaps mixed with the soil? If that is the case, I suggest that you contact your local Cooperative Extension Service office. In fact, contacting them for diagnosis would also be a good idea or, if available in your area, Extension Service Master Gardeners can also help in diagnosing problems and finding solutions.

Plant Spring flowering bulbs

When is the best time to plant tulip bulbs? Can I do it in the late fall, and what other bulbs can you plant in fall?

Bulbs which bloom early in the spring, including the tulips, are best planted in the fall. Here in New Mexico we recommend planting in October, but if it is not possible to plant by then, to plant by Christmas. So, plant from October until the soil freezes. The earlier planting is preferable because the bulbs produce roots in the warm soil in the fall before the ground freezes. When the air is getting quite cold, the soil retains considerable heat and allows this growth of roots. A good root system helps the bulbs to establish and produce a good floral display in the spring.

There are other bulb-forming plants which bloom in the fall These include daffodils, crocus, dutch iris, snowdrops, glory-of-the-snow, hyacinths, alliums (ornamental onions), and many others. Some of these produce corms which are bulb-like but not true bulbs. Never the less, they bloom in the spring and are appropriate for spring bloom. Even lilies, which bloom in late spring or summer, may be planted in the autumn.

Be sure to prepare a good planting bed. If the soil is very sandy or mostly clay, add compost to improve the soil and apply a source of phosphate below the bulbs. Don't add much nitrogen fertilizer. Be sure the bulb bed doesn't stay soggy, but also don't let it dry out, especially in the late winter when the bulbs are becoming active below the surface preparing to bloom.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!