January 30, 2016
I moved from Illinois and have been here for eight years. I miss the dirt up north. My yard here is rock filled and difficult to dig holes. Every year I buy perennials and annuals and put them in my front yard with Southern exposure and they proceed to expire. I have luck with trees I plant but not much else. Please help. I'm tired of throwing my money away and not having my plants to show for it.
Remember that the foundation to the garden is the soil that the plants have to grow in. Some Arkansans are blessed with deep, rich soil, but many of us have our fair share of rocks. A rocky soil is not a great environment for plant growth. Amending the soil, building raised beds or a combination approach should give you more success. I would also suggest testing the drainage of the beds you have. Dig a hole about the depth you would plant in, then fill it with water until the water stands. In a well-drained soil the water level should go down an inch per hour. If the water gushes out to fast, then it is hard to keep the plants watered in a dry summer, and if it stands for days, the plants are swimming when it rains. Both scenarios are not ideal for plant growth. Raised beds help here as well, since you bring in the media you want to grow in and you can manage water issues better.
November /December 2015
My house is built on five feet of what is called fill dirt. The dirt is compact, lifeless and very difficult to dig into. I would like to plant some ornamental trees next to the house. In particular I would like an ornamental cherry. My guess is I would have to dig a huge hole and fill in with good soil. I am worried what will happen when the roots eventually try to move out and hit the wall of fill. Will the tree die? Is there anything I can do or are there plants that like fill dirt?
Keep in mind that the foundation to a garden is its soil. If you have poor soil, then amending it will help. You do not want to dig a hole and throw away the fill and backfill with good soil. You want to work with the pitiful stuff you have and amend it and make the soil as homogenous in as large an area as possible. If you have a blank slate—nothing is planted yet, then bring in a load of compost and till it in with the fill. Sometimes the soil gets so compacted after construction that running an aerator over the area can help. Compost can work wonders in lightening up heavy soils and adding some organic matter. When planting, try to amend at least three times as wide as the planting hole to help in root spread. The key is the wider the area can be amended, the better. Roots spread outward much more quickly than they grow deep. But mix in your amendments, don’t totally discard what you have. If you throw away what you have and plant in good soil, you are basically containerizing the plant in the ground. The roots will stay in one spot, and water flow will vary based on soil type. Good luck. Over time, you can create great soil.
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.
The soil is the foundation of a garden. The healthier the soil, the healthier and more resilient your plants will be. Too many of us in Arkansas are blessed with more rocks than soil, but even those who do have decent soil often lack organic matter. Building up a strong soil and amending with organic matter in the form of compost, gives plants a better start in life and makes them easier to maintain. When amending soil, it is best to blend in your amendments with the existing soil. Creating a homogenous mix will encourage rooting better than layering in different soil types. Fall is also an excellent time to test your soil to find out what the pH is and determine nutrient levels, so that you are prepared for the next growing season. The pH of the soil determines the level of acidity of the soil. It is measured in a range of 0 – 14. 7 is considered neutral, while below 7 is acid and above 7 is alkaline. Most plants like a slightly acidic soil, between 6-6.5. Blueberries and azaleas like it even more acidic, getting in the range of 5 – 5.5. Many soils in Arkansas are acidic, and we occasionally need to add lime to raise the pH. A soil test will determine whether you need to lime or not. It will also tell you how much lime to use. Lime that can be mixed into the soil will give quicker results, than lime that is laid on the soil surface. To test your soil, take slices of soil from the surface down around six inches. Get soil from 6-10 different spots in your yard or garden for each sample you are taking. Mix it together and take one pint of soil for each sample into your local county extension office. Many gardeners test their lawns, vegetable gardens and flower gardens separately, since they treat them differently. Within two to three weeks you will get a computer printout mailed to you with the results, and recommendations on what to do.
I have cleared some land that is extreme clay. I have sand left over from a building project. If I spread the sand on the soil will it make any difference in the clay?
Sand and clay make concrete. Try adding compost to the clay to lighten it without the compaction issues. Shredded leaves also could be worked in this fall. A little sand mixed in with the compost would be ok, but don’t just do sand and clay.
I live in a part of Arkansas that allows me to burn leaves. I do so regularly and I also recently burned a wood pile. Can I use some of these ashes on my flower beds and on my garden plot? If so how much would be advisable?
A little bit goes a long way. Wood ashes tend to raise the pH of the soil, so don’t use them around acid loving plants and don’t add additional applications of lime to the soil if you are using them. Ash also contains salt, so large amounts would not be beneficial to a garden. Composting the ashes along with leaves and other raw materials can help to dissipate the salt issues for later use, but have it tested to determine pH before using. Therefore, when using wood ash, a light layer is all that is needed. Avoid using it around azaleas, blueberries and other acidic lovers, and don’t use it in your vegetable garden where you grow potatoes, or you may have potato scab—which occurs when you raise the pH.
What is the recommended rate of nitrogen per 1,000 square feet per year for annual color beds?
When we talk about fertilizing annuals, we usually want to use a complete fertilizer as opposed to a nitrogen only fertilizer. With the huge range of fertilizers that are on the market, and the various forms—granular, slow release, water soluble, etc., it is best to find a product you like and follow the label directions. I like to start the season with a slow release product (often 20-20-20) and follow that up with regular applications of a water soluble form. The key with annuals is to push them as much as possible to get the most flowers.
HELP! I bought a beautiful pink hydrangea four to five years ago and it's now turning blue. I don't want blue! I want pink! I never listened when I was told years ago that the color can be manipulated by soil content. Please tell me what to do to it and how long will it take to take effect? I assume it will be next blooming season
Hydrangeas change color based on the pH of the soil. Since many soils in Arkansas tend to be acidic, most of our hydrangeas are blue. If you want pink, you need a more alkaline soil. The way to raise the pH is to use lime. Sprinkle lime around the plant, and if possible try to lightly work it in. Even poking some holes around the plant sporadically and then putting in some lime can speed up the process a bit. Lime is slow to move through the soil profile, so anything you can do to help would aid in the color change.
I want to have soil tests run on soil samples from my daylily flower beds. How do I go about it?
To take a soil sample from your daylily beds, go to five or six different locations in the bed and get a slice of soil roughly four to six inches deep. Mix all of these together and take one pint to your local county extension office. If you have a problem spot in the garden, you can take a separate sample from that location to compare to the rest. There you will fill out a form, and they will send it to the soil testing lab, and you should have a computer printout back within two to three weeks.
Our daughter has moved in to her great grandmother's house and would like to reclaim the garden from the weeds and Bermuda grass so we can plant it next year. How do we do that and can we keep the Bermuda grass in the yard and not in the garden?
If you aren’t planning to use it until later—even this fall, you can solarize the site now and kill out most of the grass and weeds. I would scrape the surface free of as many of the weeds and grass as possible, then till the soil and wet it thoroughly. Once wet, cover the site with clear plastic, getting firm contact between the soil and the plastic. Weigh down the sides with soil, rocks or bricks to exclude air. Leave it covered for two to three months this summer and you can generate enough heat under there to kill out the weeds. You could then plant a fall garden, or if you want to wait until next spring, leave it covered until you plan to plant. Bare, exposed soil tends to invite weeds and grass.
I'm new to Arkansas and have bought some acreage north of Batesville. It includes bottomland and a raised meadow (the grassy knoll) which I fear is a huge gravel pile covered with a little topsoil. Don't know that, but I fear it. When I dig, I immediately hit marble sized rocks. I have mail ordered some pecan and chestnut trees. Both say plant in well drained, moist soil. I'm guessing that the grassy knoll will drain well, but I don't know if it is suitable for my nut trees. By the way, the adjoining land is covered in cedar and oak trees. What do you think?
Just looking at soil and the lay of the land, really doesn't indicate internal soil drainage. You need to dig a hole as deep as you plan to plant your trees then fill it with water until the water stands. See how long before the water drains. That should give you an indication of drainage. Planting, much less digging, and then growing can be a challenge in extremely rocky soil, but much of Arkansas is in the same boat, and we have lots of plants, so it is doable. Get a soil test, test for drainage and see if you can amend the soil in an area at least three times the width of the planting hole with compost, incorporating that with the existing soil. Give your pecan trees plenty of room to grow, since they are large trees at maturity.
Could you please let me know how to get the soil in my flower beds tested? Last year, I planted many annuals and perennials and they did not bloom well.
Dig down six inches and take a slice of soil from several areas of the flower bed. Mix them together and take a pint of soil in to your local county extension office. They will send it to the soil lab and you will have a computer printout telling you what to do in a couple of weeks.
We built a landscape block flower bed approximately 12” high around a large red oak tree 2 years ago. My uncle said we would kill the tree because we used too much dirt and should slowly raise the amount of dirt in the bed. The tree died less than 1 year after we established the raised bed. I did have several red oaks die the previous year due to the "red oak borer insect". My question is this; can you build a raised bed around a mature oak tree without killing it? My wife and I have another tree that we would like to landscape, but do not desire to kill another tree.
I wish there were an exact formula for the total amount of soil you can build up around an existing tree. Unfortunately, there are too many variables, such as type of tree, soil type, size of bed, etc. As a general rule, we really don't recommend adding more than 1-3 inches of soil around an existing tree, and even that in a limited fashion. If the flower bed is relatively small, it usually isn't a major cause of concern. Keep in mind that a tree has an extensive root network, and that the feeder roots should be far and wide under a trees canopy. If the bed is small and not overly deep, I would suggest going for it. I would avoid piling up huge amounts of soil next to the tree trunk as excess moisture on the trunk can lead to decay.
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