Xtremehorticulture

How to Get Rid of Bermudagrass Weeds in a Tall Fescue Lawn

Q. How can I get rid of bermudagrass now, growing in a tall fescue lawn. Bermudagrass invasion of tall fescue due to irrigation and mowing height. Keep mowing height at least 2 inches for tall fescue and keep it full and lush. A. The best way to get rid of it in fescue is to cut it out if possible and then seed the bare spots after the Bermudagrass has had time to die. The best time to do this would be about April or May when Bermudagrass is starting to green up. You’ve got to kill the Bermudagrass when its alive, which starts growing in late spring, and seed the bare areas after all the grass in that area dies. That’s tricky because Bermudagrass is a warm season grass and doesn’t start growing until about mid-March or early April. It’s easier to control fescue growing in a Bermudagrass lawn while the bermudagrass is dormant (sleeping and dead looking). The fescue in the lawn is cool season so you can begin seeding when it’s cooler. But bermudagrass is warm season so it doesn’t “wake up and start growing” until late spring. If you want to try that then I would recommend spraying Roundup (its the only systemic grass killer available) in spots where the Bermudagrass is growing in the late spring and wait about a week. Don’t use Roundup combined with any other weed killer. Just plain old Roundup. The systemic Roundup translocates and kills some of the roots of bermudagrass.  First, cut the grass in the Roundup-applied area shorter and seed directly into those spots. Because Roundup is systemic and slow acting it will continue to kill the bermudagrass. The label on Roundup prevents you from seeding any sooner than this. You should start seeing the fescue pop up from seed in about 7 to 10 days as the grass in those spots continues dying. What to Do? 1. Mow the area shorter. 2. Spray Roundup over the area without any other weed killers in it. Just plain old Round-up. The grass wont die for 2 to 3 weeks.  3. After one week, seed a high value tall fescue seed in the same area. The grass you sprayed will look like it is alive but it is dying. I would mow the area shorter, somewhere between a half to an inch tall, and apply ammonium sulfate (21-0-0) in early March. The Bermudagrass likes warm weather, as well as nitrogen fertilizer, and it will start turning green a couple of weeks earlier than when it is taller. Use a high-quality tall fescue variety to seed in those spots. The grass will not be dead yet but it’s dying, and you have to trust that it’s dying. As the new fescue seed is coming up you will see sprayed areas start to die or turn brown. You can safely seed into Roundup-applied areas 7 to 10 days after the spraying has been done. The tall fescue and Bermuda does not look dead yet, but they are dying. You can’t start killing Bermudagrass until after it starts getting green in the spring. Preventing Bermudagrass Invasion In the future keep your mowing height between two and three inches. Keep the lawn thick to choke out any invading Bermuda grass. To do this apply fertilizer to fescue lawns at least 4 times per year; Valentine’s Day, Labor Day, Memorial Day, and Halloween. The fertilizer to use is a 21-7-14, between half to 3/4 of the bag rate if you are returning the clippings to the grass (not bagging). The rate on the bag may be too much fertilizer. Don’t give the edges of your lawn of bevel cut because it encourages in Bermudagrass invasion. Instead use a steel edger perpendicular to the edge of the lawn.

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Tree Planting Requires Proper Hole Preparation in the Desert

Q. I had a boxed mastic tree planted recently. I didn’t like how it was planted. It was planted with the trunk not straight, the top of the roots exposed, the soil in the hole was dry, and I had them remove the bottom of the box. They were going to plant it with the bottom of the box still under the root ball. Mastic tree planted too shallow. Also the area is very small for such a large tree. A. I looked at the pictures you sent to me, and I agree it was not planted well. Sloppy planting. The hole was dug too small, and it was not planted deep enough. About 30% of the soil should be amended for drainage and moisture retention. Out of sight, out of mind. The soil surrounding your tree may or may not have enough amendments added. Watch this video on planting trees in Arizona that I thought was pretty good. Mastic (Pistacia lentiscus) trunk was planted with the trunk at an angle which is less of a problem than the exposed rootball (above).             Mastic is related to pistache (Pistacia lentiscus). Like all pistache trees, it is mesic in its need for water. This tree is Mediterranean in origin rather than western Chinese or Central Asian. Water requirements for both are similar and both develop red fall color. It grows well in a lawn where it gets plenty of water or surrounded by other mesic shrubs for the same reason.             When planting on a slope, the lowest side of the hole should be used for judging the hole depth. Add water at the top and sides of the hole, not the bottom. This tree is fine growing in soil covered in rock. If this tree shows signs of poor growth in a few years, add a layer of compost on top of the soil and water it in. Water should be applied on the “uphill” side of the tree but three feet at least from the foundation of the house. Dry Hole Problems             The problem planting in a “dry hole” is removal of air pockets. Dry soil pushed into the rootball (and using the butt end of a shovel to shove it further) may or may not remove them. Usually not. When planting in a slurry of soil the air pockets are removed at planting time (look for the bubbles), less “transplant shock”, and less concern about tree stability (staking) after planting. Air pockets in the soil will not do that. Wet the Soil             Making a slurry is easy to do. Just use a hose during planting. Sometimes a dry soil can be compensated in the first few months by circling a moist rootball with a “moat” or donut on top of the rootball when planting and wetting the soil after planting. Either that or apply water slowly or several times to get it to soak in.             This tree grows about 25 feet tall with about the same spread when fully mature. Pay attention to branch direction and the house when planting. Dig the planting hole at least three times the width of the plant container. Amend the soil removed from the planting hole with “organics” of some sort to keep the soil loose, friable, and well drained after planting. How Close to the Home?             I wouldn’t plant it any closer than 8 to 10 feet from a house to accommodate the watering and branch growth. Trees should be planted as close to vertical as possible. When trees are planted from a wooden box, usually the bottom of the box is removed first, and the sides are removed after lowering it into the hole. Fill the hole half full and then ADD water to make a slurry. Never add dry or hot soil to a planting hole.

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Plant Replacements in the Fall or Spring

Q. I removed two Italian Cypress trees (harder project than I imagined, especially the stumps). When is a good time to replace them, how big of a hole should I dig, and how should I prepare it?  A. I can imagine that was a very difficult job removing Italian cypress. Probably the easiest way to do it, yes I know it’s already done, is to cut it off and rent a stump grinder and grind out the stumps. The wood grinding’s mixed with soil makes a fabulous mulch.             The best time to replant is in the fall months but the problem is plant selection. There is usually not much to pick from. The best stuff is gone and the nurseries don’t want to be stuck with anything through the winter and availability of plants from wholesalers is limited to stuff that didn’t sell. But you can still find things if you’re willing to look around.             An alternative to Italian cypress is the Skyrocket Juniper. It is hard to find but stays narrow and smaller. They used to be popular 30 or 40 years ago. This is not a desert adapted tree so it will require soil improvement and I would mulch it with wood mulch at the base on top of the soil. I have never seen it planted in our hot desert climate but I don’t see a reason it won’t work with some soil preparation, decent irrigation and wood mulch.  http://www.monrovia.com/plant-catalog/plants/1715/skyrocket-juniper/ You should not have a problem planting in the same holes if the Italian cypress he removed was healthy.             Dig a hole 3 to 4 times the diameter of the container that the plant comes in. If these holes already have quite a bit of organic matter in them… You can tell by the color… Then don’t add anything. But otherwise mix the soil you take from the hole 50/50 with compost. The best compost out there locally for doing this is Viragrow compost in North Las Vegas. Viragrow compost available in North Las Vegas

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Apply Rose Fertilizers Now

Q. In previous years I started fertilizing our roses in March. They performed poorly last year so I want to feed them earlier. Is it ok to start now, and if so is there any special formula or nutrients required for the first feeding? A. March is okay but it would be nicer if you applied fertilizer a bit earlier, say in late January or early February. Roses perform better in soils enriched with compost, applied fertilizers high in phosphorus and iron and wood mulch several inches deep. To get award winning roses follow advice from Rosarians Rosarians who want high quality roses fertilize multiple times during the year. The first fertilizer application (light) is at bud break in the spring, a second one when the flower buds have developed and not yet opened and a final one in the fall from late August through September. A number of them like fish emulsion and Epsom salts as additional feedings through the summer months when roses go into a kind of high temperature dormancy. Use a good quality rose fertilizer such as Peters or Miracle Gro plus an application of iron chelate, preferably EDDHA, applied to the soil. If you are applying iron to the foliage you will have to wait until they fully leaf out in about March. Foliar sprays use a spreader or liquid detergent added to the spray solution at the very end of the mixing.

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Large Boxed Tree Needs Extra Help

Q. Should a newly planted 36″ boxed purple robe black locust tree have it’s nursery stake removed? I sent you a picture of it. Readers Purple Robe Black Locust staked. A. Larger trees need their roots stabilized for one to two growing seasons and then the stakes removed. In your case the tree has poor trunk strength since the trunk has no taper to it and the trunk will snap in high winds.             Immobilize the roots by re-staking the tree. Let side branches develop along the trunk to improve trunk taper and strengthen it. Normally, a tree with good trunk taper can have its stakes removed after one to two growing seasons. A tree with poor trunk taper will require a longer period of staking to strengthen the trunk AND give it solid rooting into the surrounding soil.             Allowing side branches to grow along the trunk helps promote taper in the trunk reducing its need for staking after one season.             Ideally, the tree should have small stems growing from the trunk covered in leaves, removing them only when they reach about pencil diameter. This increases stem taper, reduces the possibility of shear or snapping in high winds.              Trees also need to “sway” in the wind. This swaying or movement of the trunk from side to side also helps to develop taper in the trunk. But the roots of the tree need to hold the trunk in place at the bottom.             This tree will need to be staked for awhile to keep the trunk from snapping. Probably at least one season. I would probably restake the tree with either two or three stakes to support the trunk and keep it from bending to the point where it could snap and immobilize the roots. Large trees usually need stakes to support the trunk. The stakes should be driven deep enough so that they are in solid soil. The support from the stakes should be low enough to allow the top of the tree to move but keep the rootball from moving.             Two methods used for re-staking include a two to three stake method with the stakes driven into the solid soil beneath the rootball. The other way is to use guy wires to stabilize the tree. I supplied pictures that I will also post on my blog.             This next year let small branches grow from the trunk if they develop. These will increase the strength of the trunk and help reduce sun damage to it as well. Remove older branches from the trunk when they get larger than a pencil in diameter. Cut them off flush with the trunk. Do not use pruning paint.

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The Proper Way to Prune and Hedge Oleanders

Formal oleander hedge, no flowers Q. Would you please comment on the proper method and timing to prune and hedge oleanders.  This is two questions. A. There are two types of hedges; formal and informal. You have to make up your mind which kind you want. Formal hedges are pruned with a hedge shears while informal hedges are pruned with a loppers or even a pruning saw. Formal hedges are supposed to be pruned so that the bottom is wider than the top but they are maintained in a tight boxy shape. To maintain them properly, formal hedges need to be pruned two to three times during the growing season to keep the new growth restrained and maintain that boxy shape. Oleanders flower on current season or summer wood             Informal hedges can be pruned every two to three years, most of the pruning is done at or near the soil level and is done during the winter months. Formal hedges are best done on nonflowering plants that have small leaves. Informal hedges are best served by other types of plants, particularly those that flower during the summer. You can prune any plant used for hedging in any manner you want but there are some big advantages in picking the right type of hedge for the right plant.             Oleanders flower on new wood. In other woods after the winter rest its new growth supports the flower throughout the summer. Formal hedges, since they are pruned to maintain that boxy look, are pruned during the time of year when it is growing. If it wasn’t pruned then, in a few short months it would no longer be in that boxy shape. The problem you can see right away is that in picking a formal hedge for oleander you will prune off most of the wood that supports flowering so it will be pretty much a green hedge. Shubs in this streetscape are “hedged” for no apparent reason other than creating more income             If you want to enjoy the flowers then convert it to an informal hedge. The problem is that 95% of the maintenance companies DON’T KNOW HOW TO PRUNE FOR AN INFORMAL HEDGE.  And it is very simple, there is far less mess, the cleanup time is very short but you ONLY HAVE TO DO THIS EVERY TWO TO THREE YEARS.  Now if I were a maintenance company, which type of hedging would I like to charge for. Hmmmm…. Once every two to three years or two or three times a year….             Now if I really want to do a lot of work then why not make ALL the plants in a landscape boxes! That way I would have to prune them several times a year rather than once every two to three years! If I can’t make money mowing a lawn any more then lets charge for making all the plants in a yard into boxes… or gumdrops.             Pruning for an informal hedge is quite simple. During the winter, once every two to three years, remove one third of the plant at or near the soil level. Pick 1/3 or ¼ of the largest stems and cut them off. This will only work on shrubs that have lots of stems coming from the ground. On plants which have a single stem or only two or three coming from the ground then you have to move this technique higher in the plant and inside the canopy.

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