Posts

Knowing How Much to Water, Part II: #itsSTILLcomplicated

Image
Southwest Yard & Garden by Dr. Marisa Thompson

Question: How much should I be watering my trees?  -  Multiple Gardeners from All Over NM
Answer (Part 2): In last week’s column, we learned about how the type of soil in your garden affects tree water requirements. Now we will focus on other considerations, such as rates of water movement, tree species, age, canopy size, and seasonal fluctuations in water needs. Plants take water up from the soil through their roots all the way to the leaves where it is released into the air. Transpiration is the process by which a plant loses water, primarily through pores in the leaves called stomata. This is a necessary process that involves the use of about 90% of the water that enters the plant through the roots. The other 10% of the water is used in chemical reactions, like photosynthesis, and in plant tissues. Transpiration is necessary for mineral transport from the soil to the plant tissues, for the cooling of the plant through evaporation, for mov…

Knowing How Much to Water, PART I: #itscomplicated

Image
Southwest Yard and Garden Knowing How Much to Water, PART I: #itscomplicated

(partialreprint from October 2017)

Cottonwood leaf near Hillsboro, NM in September 2017. Although native to our region, cottonwood trees are no longer recommended for most of our ornamental landscapes because of their high water needs. Photo credit M. Thompson.



Question: How much water does my tree need?  - Multiple Gardeners from All Over New Mexico
Answer: I’ve said it before, and I’ll say it again: It depends! Considerations include the tree species, age, growth phase (e.g., dormant, bud break, leaf senescence in fall, etc.), soil type, time of the year, temperatures, winds, other weather-related events like recent rain, hail, or snow, and so on.
Even if you know the species of your tree and try to look up water requirements, you will likely find either a painfully vague answer like “moderate” or a complicated one. For example, in Judith Phillips’ revised New Mexico Gardener’s Guide the watering directions for d…

Managing Aphid Outbreaks on Fruit Trees (and Other Plants)

Image
Southwest Yard & Garden

Peach tree stem infested with aphids is likely going to defoliate completely, but this early in the growing season there’s a good chance it will bounce back and be covered in new leaves in no time. Photo credits M. Thompson.

Question: What’s causing our peach tree leaves to wither and curl up completely and should we also be worried about our apricot trees nearby? -Lorraine J., Los Lunas, NM Answer: Looking at the sample you brought in, the leaf curl on your peach tree branches is pretty extreme, and when I turned over and uncurled the leaves I found a ton of chubby green aphids hiding underneath. Some of the leaves, especially at the tips, are stunted and probably won’t fully expand after so much damage. Another aphid clue is the shiny, sticky coating on many of the leaves. The sticky shellac is called honeydew, which is a darling name for aphid excretion or – pardon my French – poo. In my first New Mexico summer I was walking down Lomas Ave. in Albuquerque on …

Shocking Houseplants When Transitioning Outdoors

Image
Southwest Yard & Garden Late April to early May is usually a safe time to move houseplants outside in most of New Mexico, but transition carefully and watch the forecast! Reprint from April 2011. Written by Dr. Curtis Smith, retired NMSU Extension Horticulture Specialist, with additions by Dr. Marisa Thompson.  Question: Is it safe to put houseplants outside now? After I moved my plants outside last year most of the leaves died. - M.J., Albuquerque Answer: In the Albuquerque area, it will soon be safe to put houseplants outside for the summer. If you are in the valley or high-elevation areas, you may need to wait until the second week of May. Gardeners in southern New Mexico can be more confident moving plants outside already (except those at high elevation). In northern New Mexico, gardeners should wait another month or more. In any event, you should watch the weather reports and be prepared to move plants back indoors or cover them. Frost and freezes are increasingly unlikely, but not…

Picky Picky: Selecting the Right Fruit Tree for Your Garden

Image
Southwest Yard & Garden by Dr. Marisa Thompson



Question: What fruit trees are recommended for my area? -Karena, Dulce, NM Answer: Last week I offered tips for protecting existing fruit trees with bursting buds and open flowers from late frosts (visit https://nmsudesertblooms.blogspot.com/2019/03/late-frost-fear-protecting-fruit-trees.html). In commercial fruit production systems, growers can justify the costs of running serious equipment to keep the bud tissues from freezing, like wind machines or a sprinkler system that showers the canopies through the night, but these options only work when temperatures are expected to stay just below freezing. Colder spells may make matters worse! The actual best thing you can do to protect those buds and maximize yields is select trees carefully before you buy. Getting a reliable crop from many popular fruit trees can be tough in New Mexico. This is especially true of the earlier-blooming ones like almond, apricot, Japanese plum, and sweet cherry…

Late Frost Fear: Protecting Fruit Trees from Losing the Entire Crop to Freeze Injury

Image
Southwest Yard & Garden by Dr. Marisa Thompson
Question: How can I protect my backyard peach tree from losing fruit to late frosts? -Submitted via Patrick Kircher, Roosevelt County Extension Agriculture Agent, Portales, NM Answer: This is a tough one. There’s lots of advice out there for things that might help (emphasis on the “might”). Your options for protecting those precious buds and flowers really depend so much on how old and big the tree is, what stage of development the buds are in, how cold it’s going to get, how high wind speeds get, and how long the cold lasts. Because eastern parts of the state might get a cold snap this week, I’m focusing on what to do to protect existing trees in your yard from late frosts. In another column, I explained the underlying principles in more detail and offer suggestions for how to select trees better suited for our challenging environment. Click here to link to that column! There are some tried and true tricks for maximizing fruit load by pr…

Pruning Pomegranates

Image
Southwest Yard & Garden by Dr. Marisa Thompson

Question: When should I prune my pomegranate tree and how much wood should be removed during pruning? -Extension Master Gardener Trainees in Valencia and Bernalillo Counties Answer: Pomegranates (Punica granatum) are monoecious plants. Monoecious is a flowering term that means it has both male (pollen-forming) and female (ovary- and fruit-forming) reproductive organs on the same plant. The individual flowers can be perfect, meaning both male and female parts are found together in a single flower. Other flowers found on the same shrub can be imperfect, meaning they are single-sex. The imperfect flowers on pomegranates are male only, so they produce pollen and then fall to the ground. That should make many pomegranate growers breathe a sigh of relief because it’s common to find dozens of the bright red blossoms littering the ground, blame the wind, and then worry that you won’t get any fruit this year. Those male flowers were never meant t…

Get Growing with Grapes: Considering Shade, Rabbits, Disease Detection, and More!

Image
Southwest Yard & Garden by Dr. Marisa Thompson with guest contributor Dr. Gill Giese Question: My husband and I are planting a few Marquette grape vines this year in Santa Fe. I would like to plant a tree approximately 8 feet from the vines. Could you recommend some trees that would be “a good idea” to plant close by? I read that planting a rose bush at the vines will help to indicate any diseases since the roses would get this first. Is this a good thing to do? Are rabbits a problem with grape vines? We have quite a few roaming freely. Should we protect the vines with a net around them? -Susan R., Santa Fe Answer: For the tree portion of your query, what direction, relative to the grapes, will the tree be planted? Will the tree shade the grape vines? Even if the tree is planted on the north side of the grape-growing area, it may shade the grapes once the canopy gets larger, so selecting a small tree might be helpful. Here are a few smaller-sized trees to consider: redbud (Western, Eas…