Falling Pine Needles and Moving Roses

 

Southwest Yard & Garden

Reprinted columns written by Dr. Curtis Smith

Note from Dr. Marisa Thompson, NMSU Urban Horticulture Extension Specialist and regular author of this column since 2017: When addressing horticulture questions from around the state, I often check the Southwest Yard & Garden Archives to see if my esteemed predecessor Dr. Curtis Smith tackled the same issues in past years. This week, I’ve selected two columns from November 2010 to reprint in response to recent questions I’ve received: one on transplanting roses and another on dropping pine needles. Both were written by Dr. Smith.

Reprinted from November 20, 2010

Question:

I need to move some climbing roses (Lady Banks) and honeysuckle bushes. All have been in the ground two years. When is the best time to move them? Can I move them to pots and plant them later in the year? Anything special I need to know? Thanks!

- Mary P., Las Cruces

Answer:

The best time to move these plants is late in their dormant season. If you were to move them directly to their new location, January would be a good time for you. In other parts of the state, February or March would be good times. The key is that they are dormant, but soon before growth resumes.

You expressed an interest in moving them first to pots before planting in the new site. That is possible now in Southern New Mexico. Many temperate zone plants produce significant root growth in the fall as the tops are going dormant and afterward. So, moving them to pots now will allow them to produce new roots. In colder parts of the state, gardeners can also move plants to pots, but with less benefit of additional root growth.

An important consideration is that the soil in pots (above grade) will become colder than the soil in the ground. Roots do not develop as much hardiness as the shoots. This means you should keep the pots in a protected location where the soil in the pot will not become too cold. However, do not put it where the sun will shine directly on the pots generating too much heat in the soil. Burying the pots in the ground (up to their rims) or surrounding them with straw bales will help moderate the temperatures in the pots and protect against root damage.

In January (Southern New Mexico), February (Middle Rio Grande region and Eastern New Mexico), and March (Northern New Mexico and high elevations), you can move the plants from the pots to their new growing locations. Prepare the planting site well (large area with amendments), water well after planting, and mulch the plants. New growth should develop within a couple of months.

Pine needles make a great layer of mulch under and around landscape plants. For maximum weed control, maintain a minimum mulch depth of 4 inches. Photo credit Antonio Jordán (distributed via imaggeo.egu.eu)

Reprinted from November 27, 2010

Question:

I have noticed that many needles on the inside of my pine trees have recently turned brown and are starting to fall. Is this a disease or drought? What can I do? Since the needles are falling, are they safe to use to mulch my garden?

- Concerned Citizen, Bernalillo County

Answer:

It is a regular event for needles on the inside of a pine tree (the older needles) to turn brown and drop from the tree. I checked with Bernalillo County Extension Horticulture Agent, who told me that she was seeing many pines dropping their 3- and 4-year old needles now. This is probably what is happening to your tree. Even though pines are evergreen trees, they do not keep their needles forever. Older needles fall away every year, but the loss of old needles is more apparent when the needles falling were produced in a year with a favorable environment for the development of many needles. If many needles developed 3 or 4 years ago, then the needle drop is much more apparent than if there were relatively fewer needles formed that year.

These needles are safe to use as mulch around most plants and especially perennial plants in your garden. Because pine needles contain high levels of resins, they repel water and decompose much more slowly than leaves from most deciduous trees. Their shape also helps them avoid becoming moist and composting rapidly. This makes them especially useful in areas where you will not be digging frequently. The fragrance of pine needles on sunny days is also an added benefit when they are used as garden mulch.

Some people fear that pine needles are too acidic for use in our gardens. This is not a concern in New Mexico; added acidity is beneficial in our soils. Even so, their slow decomposition slows the release of their acidity into the soil. They are definitely beneficial as mulch. They are very slow to compost, so they are often better mulch than compostable material.

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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.

Links:

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 page.

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