Spring FAQs 

7. (March) When should I plant my flowers – annuals?

Sow the seeds of annuals and/or transplant annuals after the last frost. This is, on average, around April 15th in the Albuquerque area. This date will be later in the East Mts. (mid-May) and later in the valley (early May). Watch the weather forecast to get a better idea of what to expect in a particular year. Adjust planting accordingly. Hardy annuals, such as pansy and ornamental cabbage (grown as an annual, but it is actually biennial), may be transplanted earlier. These plants can withstand freezing temperatures.

8. (March) If I have dead stone fruit trees killed by borers among my other living fruit trees, should I remove the dead ones? Can I stack the wood for use in the fireplace?

Before discussing borers, one common disease that affects stressed and/or aging stone fruit trees is Cytospora. Cytospora is a fungus that enters the trees via a wound or pruning cut. Symptoms include sap oozing out of branches with no apparent wound or boring insect hole associated with it. Branch dieback will also occur. If Cytospora is present in your trees, there is no cure. Keep the plants well-watered and prune out dead and dying branches until the tree is no longer acceptable.

One of my pet peeves is the general use of the term “borers”. I prefer not to use this term so generally. It is important to know what kind of borer and understand its biology to help determine the best course of action. Most borers will attack trees that are stressed or “devitalized” in some way. For example, trees that are not adequately watered, have girdling roots, or are not suited to our hot and dry climate are under stress. Just like humans are more likely to get the flu when they are under stress, trees are more likely to attract pests when they are under stress. The best way to prevent borers is to keep your trees healthy, well-watered, mulched, plant trees suited to our environment, and prune out dead and dying branches. No other measures need to be taken.

In this case, since the trees are stone fruit trees I will assume we are dealing with the peach tree borer. Peach tree borers are the exception in that they will attack perfectly healthy, non-stressed stone fruit trees.

Removing the dead tree is not necessary unless it is a hazard or an eye-sore. Since peach tree borers are not specifically attracted to stressed and dying trees, I would not be concerned about my dead stone fruit tree attracting more peach tree borers to my property.

If the other trees on the property are not stone fruit trees, then there is no need to worry because peach tree borers will not attack them.

If the other trees on the property are stone fruit trees, then some action should be taken. Apply a preventative spray to all the living stone fruit trees on the property. Use something with the active ingredient Spinosad. Apply only to the lower two feet of the trunk starting in mid – to late July and keep coverage through August. This means re-applying the Spinosad product every 7 to 10 days (per the label). Please read and follow the label of the product that you decide to use. If this is done every year, the peach tree borer will not infest your healthy trees.

To prevent other kinds of borers from attacking your trees, try to minimize stress to the trees by keeping them well watered and mulched.

Stacking the firewood from the dead tree is perfectly fine.

9. (March) My pine tree (not sure of type) is getting yellow needles. Should I start watering it now that winter is gone?

It is useful to identify the type of pine tree that is in question. Without this information, I will discuss some general thoughts on the matter. Several things can make pine needles turn yellow or brown. In the fall and sometimes in the spring, pine trees will shed older needles. This is completely normal. The whole tree will have a patch of completely brown needles about 10 to 15 inches in from the tips of the branches. If you touch these browning needles, the will detach very easily from the tree and you will have a handful of dead needles.

If the needles at the very tips of the branches are turning yellow or brown, there is some kind of stress on the tree. It is also important to know the pattern of yellowing. Are the needles yellowing from the tips inward or are there yellow bands on the needles? Needles browning from the tips inward are indicative of water and/or heat stress. Needles with yellow banding may have a foliar fungal infection.

Without knowing more specific information, it is impossible to answer this question. A photograph or sample would be very helpful in this situation.

To answer the watering question. . . yes! Trees (evergreen and deciduous alike) should be watered year-round, even in the winter. Water trees deeply at the drip-line. In other words, soak water in from the surface of the soil (avoid those deep-root waters) to a depth of 15 to 20 inches or so. The only thing that varies throughout the year is the frequency of watering. During the winter, you may need to water only once or twice. You simply want to prevent the roots from completely drying out over the winter. You also want the tree to have moisture to draw from immediately in the spring as the weather warms up. Keep an eye on your tree and also feel the soil a few inches deep. If your tree looks stressed and/or the soil feels “bone dry” it’s time definitely time to water! You’ll learn through trial and error how long to run the irrigation and how often to water your trees. I have a few more tips and tricks to share with folks. Just give me a call or and e-mail and we can discuss this more.

10. (March) I’ve had codling moths on my apple trees before. What should I spray with, and when? When to hang up the traps?

Codling moths are not simple to control. Their development is tied to temperature and they produce several generations per year. The timing of their activity varies from year to year because the temperature varies from year to year. Here are a few options for management.

• Do nothing

• Install maggot barriers. These look like panty-hose footies. Put on each apple you want to keep worm-free when they are only dime- to quarter-size.

• Hang a pheromone sticky trap out when trees are in full bloom. This may trap out enough of the male moths to provide more worm-free apples than doing nothing.

• Spray (use product with active ingredient Spinosad) 4 times about 10 to 14 days apart starting 2 weeks after petal fall. This method may be more effective some years depending on the temperatures. Other years, the spray times may be out of sync with the moth’s life-cycle.

• Hang a pheromone sticky trap when the trees are in full bloom. Monitor it for codling moth daily. Record daily temperature maximum and minimum. Calculate degree days. Spray 250 to 300 degree days after biofix. Spray again at 1250 to 1310 degree days after biofix. For more information visit: http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7412.html or contact the County Extension Office for more information on what biofix is and for more details on monitoring.

11. (March) What soil amendments should I put in when I’m planting my new fruit trees?

This is the easiest question to answer. . . nothing. If the tree is bare-root, simply dig a shallow and wide hole, spread the roots out in the hole, fill it in with the same soil you took out, and water it in. Ensure that the shallowest root is no deeper than 1 inch below the soil. Planting a tree too deeply can be detrimental. After filling in the hole and watering, poke your shovel handle in the watery hole a few times to remove air bubbles. Mulch.

If the tree is containerized, the best thing one can do to give a new tree the best start in life is to inspect the root ball after removing the tree from the container. Take a hand fork, hand cultivator, or pruning shears and work around the entire root ball from the outside in (tear it apart). Straighten out any twisted roots without breaking them. If you can’t straighten them without breaking them, prune them off so that they are relatively straight. After working through the entire root ball (expect to spend an hour or so on this), correcting any root flaws, plant as I described for the bare root tree.

12. (March) I think my soil is “bad.” How can I get it tested?

Soil is complex. Soil is the foundation of our gardens. If you have a problem, such as excess salts or sodium, this can greatly reduce the health of your plants and it is a frustrating experience. Getting your soil tested, even if there is no apparent issue, is a good idea. A soil test will shed light on the nutrient status, pH, texture, etc. of your soil. You will know whether applying fertilizer or amendments is actually needed. You may contact the Bernalillo County Extension Office at 246-1386 for information on how to have your soil tested professionally.  Here is the best way to take your sample: Collect a “composite” sample from the area of concern. This means collecting a scoop of soil from at least 5 sites in your yard. Always scoop the soil to the same depth (be consistent). Take the samples from the depth that your plants’ roots are experiencing. I recommend sampling to a depth of about 0-6 or 0-8 inches. Don’t collect any surface litter, push that aside first. Mix together all 5 “subsamples” and scoop 2 cups worth out.

13. (March) What type of grapes should I plant here in Alb?

Please see the following NMSU publication : http://aces.nmsu.edu/pubs/_circulars/circ483.pdf

Some questions to ask yourself are, “What time of year do I want my grapes to ripen, early-, mid-, or late- season? What color berry do I want, black, red, white, golden, green? What do I want to use the grapes for, table grapes, making wine, making juice?” Once you hone in on your objective, this can help narrow down your choices of what to plant. The second important consideration is whether you have a suitable site to plant grapes. Grapes prefer full sun and well-drained soil. If you do not have a suitable site, plant something else instead. Finally, American x European hybrids combine the cold-hardiness and alkalinity tolerance of the American and European varieties respectively. If possible, try to choose an American x European hybrid.

14. (March) When and how should I prune my roses?

How to prune roses depends on the type that you have (climbing, floribunda, or hybrid tea). Please refer to NMSU publication h-165 for detailed information on rose care are diagrams on pruning each type. http://aces.nmsu.edu/pubs/_h/h-165.pdf

In general, garden roses do not go fully dormant, so it is important to prune them 2 weeks to 1month before the last killing frost. So, this means you would prune them anywhere from mid-March to the beginning of April. If you prune in the fall or winter and then we experience a warm spell, the roses may vigorously resume growth (pruning stimulates growth) only for the tender new growth to be killed back by frost.

15. (March) Can poinsettias be grown again to bloom? How? Are they hardy?

Poinsettias are not cold hardy. In fact, the coldest zone they can handle is 10! Avoid exposing them to cold drafts in your house. Even this can shorten its life. They can be coaxed into blooming again, but it’s not easy. Here is a publication from NMSU with extensive information on poinsettias, http://aces.nmsu.edu/pubs/_h/H-406.pdf. In summary, after tiring of the poinsettia plant after the holidays, gradually withhold water until the leaves wither and die and finally the colorful bracts wither and die as well. Put the plant in a cool, dry, dark place until spring. In the spring, take the plant out of storage and trim the stems to about 6 inches. Repot the plant in fresh potting soil. Place in a warm sunny spot in your house. After all danger of frost, take the pot outside and sink it into a warm, lightly shaded flower bed (don’t take the plant out of the pot). Keep it well watered and fertilized. As fall weather approaches, take the plant back inside and place in a sunny location. In late September or early October ensure the plant receives total darkness for 14 hours a day for 4 weeks. During the day, place in a sunny and warm location. The poinsettia should develop colorful bracts for the holidays!

16. (April) When do I spray for the pine tip moth?

Pine tip moths feed on and destroy new growth (terminals) of pines. If you suspect infestation has occurred, look for red-brown dying branch tips. Snap off one of these tips and look for a small reddish-colored caterpillar living inside the shoot. This is the pine tip moth larvae.

However, the best time to spray for the pine tip moth in Albuquerque is (before you notice any damage) the last week of April and again the last week in June. Before you spray, consider a few things. The moth is not a strong flyer and won’t fly over about 15 feet. If you have a large pine tree that taller than 15 feet, spraying is not necessary at all. Also, consider the type of pine you have before you spray. The pines which the moth prefers to infest are: Ponderosa, Afgan, Austrian, Scots, Mugho, and Japanese black pines. Piñon pines are less likely to be infested.

Some recommended insecticides are permethrin or imidacloprid. The Permethrin will need to be sprayed. The imidacloprid (ex: Bayer Advanced Tree and Shrub) is systemic and it is applied to the soil. Apply imidacloprid 4 to 6 weeks before you need it to be effective. The chemical is slow to translocate throughout the tree. Please read and follow all pesticide label instructions.

17. (April) We have Leland Cypress trees which are 20+ yrs. old. The bark is splitting and oozing out rust-colored ooze. Branches are coming off one-by-one; looking sparse. What is the matter?

I do not recommend planting Leyland cypress in Albuquerque. They grow very fast for 8 or 10 years, then they outgrow the resources available to them and they “crash and burn” quite suddenly. This particular Leyland lived far longer than usual (in our area). One of the common results of this decline is infection with a vascular-plugging fungus such as Phomopsis or Botrysphaeria. This tree probably has one of these fungal infections and it is in rapid decline. There is nothing that can be done to cure the infection or stop the decline. I recommend replacing this tree with one more suitable to the area.

18. (April) A friend has a large swimming pool room with plants in it that have aphids and whiteflies. Can I close the room up and use a “bug bomb” to kill the insects?

No. A bug bomb is not a good idea for many reasons. First, bug bombs spew tiny droplets of pesticide into the air and these droplets land on the surfaces of everything in the room. These droplets will only land on the upper surfaces of plant leaves. Aphids and whiteflies do not just “hang out” on upper leaf surfaces. Second, the concentration of pesticide in these bug bombs is pretty dilute and not enough to do much to the whiteflies. Third, pesticides must be labeled for the “site” in which they are used. Since this is both a “greenhouse” and a “swimming pool” site, it will be rather hard, if not impossible, to find a bug bomb labeled for both of those sites. What would be a much better idea is purchasing a systemic pesticide with the active ingredient “imidacloprid” labeled for potted houseplants. There are liquid and granular forms that may be applied to the soil. Please follow the label instructions exactly. The plant will take up the pesticide and become poisonous to those sap-sucking pests such as aphids and whiteflies.

19. (April) There are small mushrooms growing at the base of my hibiscus. Will they hurt the bush?

Pathogenic fungus will not manifest itself as large fruiting bodies (mushrooms) at the base of your hibiscus. The particular mushrooms in your yard are decomposing some dead organic material; probably an old root from a nearby stump. More likely, it’s decomposing some mulch at the base of the hibiscus. In general, mushrooms are considered beneficial soil organisms. The only cautionary note is that many mushrooms are poisonous. If you have a curious dog or child that may feel compelled to eat the mushrooms, you should pluck them and throw them out to prevent any poisonings.

20. (April) Some “animal” is eating my flower bulbs. Don’t think it is a rabbit. What to do?

You may be dealing with damage from rock squirrels or pocket gophers. There are some helpful NMSU publications on both:

Rock squirrels http://aces.nmsu.edu/pubs/_circulars/Cr-574.pdf
Pocket gophers http://aces.nmsu.edu/pubs/_l/L-109.pdf

Both mammals create tunnels. Pocket gophers will create mounds of soil and they plug the entrance holes. Rock squirrels leave their tunnels open. If there is no evidence of tunneling, then perhaps rabbits are the culprit. Excluding the pest from your planting area may work well if the planting area is small. Install a 4-foot fence (1/2 or 1/4 inch wire mesh) buried at least 18 inches in the ground. A sheet metal band 16-20 inches wide should be firmly affixed to the wire at the fence top to prevent squirrels from climbing over. If you can identify the pest based on the tunnels, there are more specific controls that may be used (trapping and poison baits). These controls are spelled out in the publications.

21. (April) How do I prune my grape vines?

You should prune your grape vines, like roses, in the spring just a little before the expected last frost (mid- to late-March or early April). Like roses, they can be stimulated to grow by pruning and warm weather.

Pruning is the systematic removal of wood in a manner that will result in a strong vine and good crops of large clusters. Nothing influences grape production more than pruning. Excessive pruning produces vigorous vegetative growth and low yield, but clusters and berries will be large. Not enough pruning produces weak growth and an excessive fruit resulting in small clusters, small berries, and poor quality.

The objective of pruning is to develop a single strong shoot with several well-placed laterals to form a permanent framework. After young vines have been pruned at planting, they are not pruned again until the following spring. Just before growth begins the second year, select the strongest cane and tie it to a stake to form a straight trunk. Remove all other canes.
From this point, training depends upon the system you select. Three of the most common are the head, cordon, and cane (four-arm Kniffin is one example of a cane system). Please see the following publications for diagrams and explanations of each pruning system.

http://aces.nmsu.edu/pubs/_h/h-303.pdf Pruning Grapes to the Four-Arm Kniffin System
http://aces.nmsu.edu/pubs/_circulars/circ483.html Growing Grapes in New Mexico

22. (April) How and when do I plant garlic?

Garlic is planted in the fall and harvested the next summer. The garlic bulb is segmented into cloves, each of which will produce an individual plant next spring. Garlic grows best in rich, deep, well-drained sandy loam soil. In the fall, plant cloves 3 inches deep and 3 to 6 inches apart in rows. Be sure to plant cloves with the pointed tips facing up. To encourage good leaf development, apply a nitrogen fertilizer along the sides of the rows when plants emerge in the spring. When the lower leaves of the garlic plant start to turn brown in early June, stop irrigating and allow the bulb to mature. In late June or early July, dig the bulbs with a garden fork. Allow bulbs to cure in the shade or braid plants together into a ristra and hang to cure.

There are generally two different types of garlic: those that send up a seed stalk (hardneck varieties) and those that don’t (softneck varieties). Hardneck varieties send up a seed stalk with a 'spathe' or paper-like capsule at the top. This spathe contains bulblets about the size of marbles. Bulblets can be planted in the early spring. These will develop into small plants that will produce unsegmented bulbs, called rounds, in the fall. Left undisturbed, a round will produce a segmented bulb the following summer.
http://aces.nmsu.edu/pubs/_h/h-234.pdf Garlic Production in New Mexico.

23. (April) My Ponderosa pine has branch tips that are yellowing and drooping. What should I do to them?

More information is needed to answer this question. Take inventory of where your ponderosa is growing. The yellowing and drooping is a general stress symptom. It could be water and/or heat stress. It the tree adequately watered (deep soakings at the dripline of the tree)? Is the tree surrounded by concrete paving that makes it impossible to water well? Is the tree over-watered? Was there any recent change to the landscaping, such as conversion to xeriscape in the past few years? Has there been any work done on the property, such as sprinkler work where there may have been trenching and severing of roots? Any of these stresses could show up as yellowing and droopy branch tips. If recent landscape work has severed roots, the only thing to be done is water the tree well and hope it rebounds. If the tree is not being adequately watered, water it. Finally, there may be some circling and girdling roots that are causing the general stress symptoms.

24. (April) My lawn has “white spots” on it. What should I spray it with?

White spots on your lawn sound like fungal growth. You do not need to spray anything on it. If the underlying conditions that encourage fungal growth are not addressed, spraying fungicides is pointless. Fungus thrives in moist, warm conditions. While we can’t change the weather, we can change how we irrigate. Irrigate early in the morning so the grass leaves have a chance to dry out before nightfall. Make sure you are not over-irrigating. Depending on the type of grass you have, you may need to water 0.5 to 1.0 inch per week spread out over 3 or 4 irrigations. Many people water every day, which is too much. For more information on irrigation of turfgrass, contact the County Extension Office.

25. (April) What is the recipe for hummingbird feeder juice?

Hummingbird solution can be made cheaply and easily at home. It should contain no more than 1 part sugar and 4 parts water. In other words, mix together 1 cup of sugar and 4 cups of water. Boil the mixture for at least 30 seconds for sanitation. Allow to cool and fill your feeder. Caution: Do not use artificial sweeteners, do not use food coloring, and do not use honey!! Artificial sweeteners aren’t nutritious for the birds. Food coloring is unnecessary and unhealthy. Honey encourages fungal growth, which can result in a fatal disease for the birds. Be sure to change the solution often (every 2 to 3 days) and sanitize the feeder. Scrubbing the feeder with a vinegar solution is effective. I like to boil a little extra water and rinse the feeder with it for extra sanitation.

26. (May) A gentleman called from the East Mts. and asked what was the white stuff he found an inch or two below the surface in the soil around a dead plant?

That white stuff is fungus, which is considered a beneficial soil organism, working to decompose the dead plant material.

27. (May) I just put in a new tall fescue lawn about 3 weeks ago. It is coming up okay, but now seems to be yellow at the tips, and going down the blade. Used compost. Watering 5 minutes twice a day.

Tall fescue is a cool season grass. This means it thrives in the spring and fall when temperatures are moderate (between 60 and 70 degrees F). Tall fescue is most easily established from seed anywhere from mid-August through mid-September. May is not the optimal time to establish fescue because temperatures will quickly become hot and weed competition is great. However, none of this actually answers the question at hand. I will assume from the wording of the question that this lawn was seeded and not sodded. Yellowing tips could be caused by a few different things; not enough water, compacted soil, salty soil, or improperly prepared soil. Much less likely, there could be a disease at work. Watering 5 minutes twice a day may not be adequate. It is important to be sure the water is actually soaking deep enough in the soil (at least 4 inches). This is easy to determine. Get on your hands and knees with a trowel and dig into the soil under the grass. Is it moist to the touch? How deeply? If the soil is dry only 1 or 2 inches down, watering is insufficient. Perhaps the soil was not properly prepared, meaning de-compacted and organic matter applied. Please see the publication titled “Turfgrass Establishment” for a thorough discussion of how to properly prepare a site for turfgrass. The soil could be salty. The only way to determine this is to get a soil test. The NMSU SWAT lab is available for soil testing. Contact the County Agent for more information. Lastly, if there is a disease at work, only trained professionals with the proper lab equipment can diagnose the disease. For more information about submitting samples to the NMSU Plant Diagnostic Clinic, visit http://aces.nmsu.edu/ces/plantclinic/submission-forms.html or ask your County Agent.

http://aces.nmsu.edu/pubs/_h/h-509.pdf -- Turfgrass Establishment
http://aces.nmsu.edu/pubs/_h/h-508.pdf -- Turfgrasses for New Mexico

28. (May) What fertilizer should I put on my lawn, and how often? Is weed-and-feed good?

Fertilizing your lawn is necessary. How and when to fertilize depends on what type of lawn you have, cool-season grass (i.e. tall fescue or Kentucky bluegrass) or warm-season grass (i.e. bermudagrass or buffalograss). The objective is to fertilize the grass when it is actively growing and able to utilize the fertilizer. Warm season grasses are actively growing during the heat of the summer. Cool season grasses are more active in the spring and fall. They are in a “lazy” almost dormant state during the heat of the summer. Regardless of whether you have a warm or cool season grass, the fall fertilizer application does the most good. If you do nothing else, do this. For warm-season grass, the fall application is sometime in October. For cool-season grass, the fall application is at the end of October or beginning of November.

For a typical home lawn situation, choose a fertilizer that is either balanced (ex: 10-10-10) or mostly Nitrogen (ex: 12-0-0 or 29-3-14). However, when applying fertilizer always think in terms of how much Nitrogen you are applying.

Warm-season grass:
Apply 2 to 3 lbs of Nitrogen per 1000 sq. ft. per year. In order to do this, you will have to fertilizer 2 or 3 times per year. Apply 1/3 of the fertilizer in May, 1/3 in July, and 1/3 in October. Or apply 1/2 in May and 1/2 in October.

For example: if you have a 1000 sq. ft. lawn and you have a 10 lb bag of 12-0-0, you have 1.2 lbs of Nitrogen in that bag. The first number on the bag represents the percentage of nitrogen by weight in the bag. This is all you need for the whole year!!! Take that 10 lb bag and divide it into roughly 2 equal applications.

Cool-season grass:
Apply about 3 to 4 lbs of Nitrogen per 1000 sq. ft. per year. Apply 1/4 in March, 1/4 in the beginning of May, 1/4 in September and 1/4 at the end of October. In this instance, you would need a slightly bigger bag of fertilizer than the previous example. A 25 lb bag of 12-0-0 has 3 lbs of Nitrogen in it. This 25 lb bag is all you need for the whole year!!!!

For assistance in calculating fertilizer requirements, please contact the County Agent.

Weed-and-feed is not recommended. Weed-and-feeds are fertilizers mixed with broadleaf herbicides. The type of herbicide varies (pre-emergence vs post-emergence or a combination of the two). Trees and shrubs with roots under turfgrass are easily damaged or killed using weed-and-feeds. Also, regularly applying herbicides without properly identifying the weed is not responsible. This encourages herbicide resistant weeds and contributes to environmental pollution.

29. (May) There are many small black spots on my Piñon needles. What is it? How do I get rid of it?

Piñon needle scale is infesting you tree. Scale insects are relatively immobile, protected by a hard or soft “shell”, and pierce and suck their liquid meal from the plant. The good news about this pest is it is specific to piñon trees. The infestation will not spread to other types of plants.

Piñon needle scale has a well-understood life-cycle. This is a great help in managing the pest. The scale lay their cottony-white egg masses on the trunk and lower branches (also check the bottoms of branches) sometime in late winter. These eggs hatch into tiny yellow sausage-shaped “crawlers” that make their way up into the branches and out to the tips where the new growth is. They settle down and become immobile black specks that you can barely see (early spring). They feed all summer and become fatter and fatter. By the fall, you can see them quite clearly as little black “beans” in the needles. They will overwinter in these protective hard casings and emerge in the late winter or early spring. The females crawl down the tree toward the trunk and the males are able to fly. They converge and mate and the females lay their cottony egg masses. The cycle continues.

When you notice the egg masses, take a pinch between your thumb and index finger and squeeze it. If the eggs end up as a yellowish sticky gross mess on your fingers, the eggs have not hatched. This is the perfect time to spray the egg masses off tree with a high-powered nozzle or take a broom or brush and remove the egg masses. Clean up anything that you spray or brush off the tree and dispose of it off-site (put in the garbage can). If you leave the egg masses on the ground, they will still hatch and possibly make their way on to your piñon on tree. If you pinch the egg masses and they are dry and powdery, they have already hatched. At this point, you could spray the tree with a horticultural oil (to smother the crawlers) or an insecticidal soap. Once the crawlers reach the tips of the branches and settle down, they are very hard to kill due to their protective “shell”. Try to catch the scale before this point.

30. (May) I have sand burrs in my lawn. What can I spray them with to get rid of them?

Sandbur is a warm-season annual grass. It is native to Europe and it has become a nuisance here. Annual weeds are much easier to manage than perennial weeds. If you can prevent them from forming seed heads by mowing them off, you will not have a new generation of the weed. However, do expect more sandbur next year despite your efforts due to a build-up of seeds in the soil. If you are persistent at preventing seed-heads from forming for several years, the soil seed bank will be exhausted and this may rid you of the problem. A pre-emergence herbicide applied in early spring before the sandbur germinates may also help control it. However, without knowing the type of grass in the lawn or more about the setting it is impossible to make a specific recommendation. Contact the Extension Agent for more info.

31. (May) My Oleander is sending shoots out from the bottom, but not leafing out at the top. Why?

Oleander can grow well in USDA hardiness zone 8 – 11, some sources indicate 9 – 11. Albuquerque is in zone 7. In other words, oleander does not do well with Albuquerque winters! I suspect the above-ground portion of the plant has been killed off due to the winter weather, but the below-ground portion is still alive. The below-ground portion is sending up new shoots. Prune out the dead shoots and encourage the new shoots to grow, or consider removing this plant and replacing it with one more suited to the Albuquerque climate.

32. (May) What can I use to kill cabbage worms?

Don't be deceived by pretty white butterflies that skip across your cabbage. Adult cabbageworm moths attach yellow, bullet-shaped eggs on the undersides of leaves. Emerging green worms with light stripes down their backs can reach 1 to 1-1/2 inches in length. They leave round or irregular holes in the leaves of cabbage and all species of lettuce.

Control these worms by applying the bacteria Bacillus thuringiensis (BT). Please read and follow all label instructions. This bacteria is relatively host-specific to these types of caterpillars, and to brownish cabbage loopers, which feed on lettuce and cole crops like cabbage, broccoli and cauliflower. The bacteria won't harm other insects or animals.

Before spraying a garden against pests, be sure populations are high enough to warrant such action and clearly identify targeted bugs. If in doubt, contact the County Agent to identify pests and determine the best control methods.

33. (May) When can I transplant my iris?

It may be a good idea to divide and replant your irises. Late summer is the best time to divide them. That is the time when their summer dormancy is ending and they are preparing to produce new roots.

You can trim the leaf fan back to 3 or 4 inches in length. Use a spade or garden fork to loosen the soil around the irises. Lift them out of the soil with the fork or spade. Break apart the irises. Cut the rhizome (thick horizontal stem that creeps along the ground) so that a single "fan" of leaves remains with only a few inches of rhizome attached. Loosen the soil in the new planting site and amend with compost. Then, plant the rhizomes so that they are at the surface or only half covered. Water them at planting, and thereafter twice per week. As winter arrives, reduce watering to once per month. In late winter, as the irises begin to grow, increase watering to twice per month. Irises are well adapted to dry conditions during the summer, and watering twice per month should be sufficient. Some gardeners water more often, but this is a time of relatively little growth, so don't overwater.

34. (May) Why are my irises not blooming?

There are several things that can cause this problem. The plants may be too crowded. As the irises grow, the clump begins to crowd itself and must be divided. Another possibility is that the surrounding landscape (trees and shrubs) may have grown and begun shading the irises. Fertilization with a fertilizer high in nitrogen will stimulate vegetative (non-flowering) growth rather than flowers. Lack of water in late winter and early spring may also prevent proper growth.

To remedy the problem, determine which of the scenarios described above is most likely to fit your situation.

It may be a good idea to divide and replant your irises. Late summer is the best time to divide them. That is the time when their summer dormancy is ending and they are preparing to produce new roots.

You can trim the leaf fan back to 3 or 4 inches in length. Use a spade or garden fork to loosen the soil around the irises. Lift them out of the soil with the fork or spade. Break apart the irises. Cut the rhizome (thick horizontal stem that creeps along the ground) so that a single "fan" of leaves remains with only a few inches of rhizome attached. Loosen the soil in the new planting site and amend with compost. Then, plant the rhizomes so that they are at the surface or only half covered. Water them at planting, and thereafter twice per week. As winter arrives, reduce watering to once per month. In late winter, as the irises begin to grow, increase watering to twice per month. Irises are well adapted to dry conditions during the summer, and watering twice per month should be sufficient. Some gardeners water more often, but this is a time of relatively little growth, so don't overwater.

When the clump becomes dense (after two to three years), you will need to divide them again. In the meantime, enjoy them as very well adapted xeric plants.

35. (May) How do I get rid of bindweed?

Bindweed is a difficult weed to manage. It is a perennial weed, meaning it persists for many years. The best approach is a combination of mechanical, cultural, biological, and chemical control methods. Frequent hoeing will eventually help weaken the extensive root system. Be careful not to just chop up the root system and spread it around. This will only spread your infestation. Provide shade to the infestation. Bindweed is not shade tolerant. Apply a thick mulch, perhaps cardboard layered with wood chips to deprive the weed of light. A biological control for the weed is bindweed gall mite. You can inoculate your weeds with the mite and after a few years, you may see some control (do not expect quick results). For more info on the bindweed gall mite, see the following publication: http://tucumcarisc.nmsu.edu/documents/cr-600.pdf. Finally, chemicals can help control the weed as well. Glyphosate (non-selective systemic herbicide) applied to vigorously growing weeds will provide some control. Please read and follow all herbicide label instructions. Contact the County Agent for other chemical options.