May 15, 2010

1 - Straw mulch can be helpful or harmful when starting garden seeds.

Yard and Garden - May 15, 2010


Is it ok to mulch the garden with weed-free straw before seeds have sprouted? Thanks!

- Bob P.


If the seeds are large (or capable of coming through the straw), mulch can help keep the soil moist and help with germination. Very small seeds or weaker plants may not make it to the light. Another consideration is that the environment under the straw will be attractive to insects and other creatures that will eat germinating seeds and seedlings (cutworms, sowbugs/rollypollies, snails, etc.). In that case, the straw will not be helpful. If you have pests that will exploit the mulch, there may be a problem. A compromise may be to apply the mulch, but keep it 6 - 12 inches away from the seeds until the plants are well established. This will help keep moisture in the soil near (but not right at the plants - so you will need to irrigate), but create a slight barrier for pests.

Spring freeze damaged trees may grow, but be patient


I have a Purple Robe locust that is about four to five years old and this spring it froze. Is there any hope for it or should I cut it down?

- Sheila C.


You did not say where you live, and since this tree can be grown in most of New Mexico, I will answer for north and south.

In most of New Mexico the Purple Robe locust should survive even if injured by winter cold. The damage may have been caused by a late frost that damaged buds as they began to grow. They may now be slow to come out as ancillary (insurance) buds replace those that were injured.

These ancillary buds normally do not grow unless the primary bud is injured or killed.

The damage may have been severe enough to freeze the branches or twigs back to the trunk, so new growth may have to come from the trunk of the tree - that will be slow. In Southern, NM, you should see growth soon, or in a few weeks in Santa Fe. Under worst conditions, even some of the trunk may have been damaged, but the locust may sprout from the base of the trunk. These trees are very persistent.

Unless you were considering replacing the tree, I would advise waiting to see if it does sprout again. Water moderately (without leaves the tree uses much less water, but does need some moist soil around the roots). After growth begins you may decide that the tree looks bad enough to replace, but it may look pretty good after a few weeks. I recommend patience.

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:, office: 505-865-7340, ext. 113.


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

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