Mulch

October 2012

I am writing to see if you can give me some tips on blueberry cultivation. I've had these bushes for four years and I keep losing one or two each year. I have watered and fertilized in the spring, then used Miracle Grow throughout the summer. Still, they keep dying on the tips and then I soon have a whole branch that is gone. Then the plant dies. These are within easy reach of the hose and I have installed drip irrigation. I had a soil test in January, 2011 which revealed a soil ph of 7.2. I added 10 pounds of sulfur per 1,000 square feet to acidify the soil. They are also mulched with pine needles. They have a few berries but last year the birds wiped them out.

I think you have a couple of issues. First of all, blueberries need a well drained, acidic soil. From the pictures you sent me, I think they should be planted a bit higher with mounds of soil and mulch—basically a raised row of soil. This ensures good drainage. While they like ample moisture, they can’t tolerate wet feet. pH is also critical. They need a very acidic soil around 5-5.5. 7.2 could cause them to die. The last picture showed some pretty yellow leaves with green veins—a sure sign that the pH is too high. The plants can’t absorb the nutrients in the soil if the pH is not in the proper range, which can cause the iron chlorosis you are experiencing. Get the pH in range, and mound up the plantings. Drip irrigation is great. When you lose a plant and dig it up, does it have any roots left, or have they rotted? Mulching with pine needles is great, but make sure the plants aren’t staying too wet and that you don’t have them planted too deep.

June 2006

I have yellow stuff about two feet around my plants. It is a soft and looks much like cottage cheese. Did I get this from my mulch? What is the best kind of mulch to use? I was told cypress.

We have had quite a few calls concerning this unsightly mass in flower beds this season. Luckily it looks worse than it is. It is a very basic organism called a slime mold. Slime molds feed on decaying organic matter. They often resemble dog vomit (another common name for the condition) or scrambled eggs. Simply rake the mulch to help dry it out or use a strong spray of water to knock them down. Once dry weather reappears, the condition will probably disappear. If it keeps reoccurring in the same spot, rake up that area and replace with fresh mulch. As to which mulch is best, it is a personal preference. Some prefer cypress, while others prefer shredded hardwood. I just avoid large nuggets which have the potential to float and often end up in the lawn area.

April 2006

I have a huge dogwood tree in my front yard. The umbrella of the branches measures about 30 feet in diameter. And it has been gorgeous this year. I am and have been concerned about exposed roots under the tree. Basically, nothing grows under the tree, except unwanted weeds. My questions are: Can I sod over the roots? Should I cover the roots with top soil and sod over all of it? Or, should I just leave things as they are? I really would like to have some sod under part of that umbrella, probably not all the way to the trunk. What kind of watering should the tree get in summer and early fall when there is little or no rain? Also, when is the best time to trim dogwoods?

Dogwood trees are shallow rooted trees and really don't like a lot of competition from other plants -- even grass. I would not cover up the roots with soil or sod. Your best bet would be to mulch the area. This helps to conserve moisture, covers up the roots, and should reduce the weed issue -- and prevents any damage from a lawnmower or weed eater. If you want to create some pockets of soil for a few perennial plants, that would be fine, but don't bring in a load of soil or you will smother the roots and damage your tree. Water regularly throughout the summer for best flower production. If they need trimming, now would be the time to do it -- immediately after bloom. Don't try to prune them into formal shapes, or do any topping, but if you need to remove low limbs or do some corrective pruning, get it done soon. Dogwoods set their flower buds in late summer through early fall.

March 2006

I have received the following email and wondered if there is any truth to it: If you use mulch around your house be very careful about buying mulch this year. After the Hurricane in New Orleans many trees were blown over. These trees were then turned into mulch and the state is trying to get rid of tons and tons of this mulch to any state or company who will come and haul it away. So it will be showing up at retail outlets at dirt cheap prices with one huge problem; Formosan Termites will be the bonus in many of those bags. New Orleans is one of the few areas in the country were the Formosan Termites has gotten a strong hold and most of the trees blown down were already badly infested with those termites. Now we may have the worst case of transporting a problem to all parts of the country that we have ever had. These termites can eat a house in no time at all and we have no good control against them, so tell your friends that own homes to avoid cheap mulch and know were it came from.

This email has definitely been making the rounds. I have gotten at least 50 questions from Wednesday – Saturday about this. While the issue is being addressed through the quarantines in place in Louisiana, things sometimes do fall through the cracks. The risk of Formosan termites becoming established through the use of infested mulch is probably low, however, it would be wise to resist the urge to use mulch from unknown sources or at least make a thorough inspection to determine if the product contains any foreign insects. Here is a response from Matthew Keppinger, Assistant Commissioner, Louisiana Department of Agriculture & Forestry. The Louisiana Department of Agriculture and Forestry, Office of Agricultural and Environmental Sciences, has quarantines in place in the Hurricane Katrina and hurricane Rita affected parishes of Calcasieu, Cameron, Jefferson, Jefferson Davis, Orleans, Plaquemines, St. Bernard, St. Charles, St. John, St. Tammany, Tangipahoa and Washington. All woody debris in the quarantined areas is going to an approved landfill within the designated quarantine area. There are a multitude of government (state and federal) agencies that are looking at this debris every day as it is deposited into these landfills. The contractors mulching and hauling the debris know the regulations and are abiding by them according to the quarantine requirements. If there is anyone with knowledge of debris moving out of a quarantine area, they should contact our 24-hour hotline @ 225-925-3763. These are serious allegations and will be taken seriously. To date, the Formosan subterranean termite has not been identified from Arkansas and it would be to our benefit to keep it out. You should be cautious with regard to any suspect mulch and make use of the above mentioned hotline if you have knowledge of any debris/mulch that has been moved out of the quarantine area in Louisiana. In addition, you should also alert Paul Shell, Plant Inspection & Quarantine Section Head, Arkansas State Plant Board @ 501-225-1598. Additional information about the Formosan termite in Louisiana is available at the link below: http://www.lsuagcenter.com/en/environment/insects/termites/formosan_termites/

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