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SRW Tip#1: Preparing Good Rose SoilRead the article this discussion is about
This archived discussion is "read only". « Previous 1 2 Next » » PatP_2 - Pat Patterson In your discussion of double digging I was a litt Pat PattersonIn your discussion of double digging I was a little puzzled. I don't know how you do it in TX but in the West and according to most authorities, the whole idea is to not mix up the lower and upper layers. You remove the top layer to a tarp or such, loosen the sublayers and add amendments and replace the top layer as it was or also amended. Please refer to John Jeavons work. -- posted by PatP_2 » Mark_Whitelaw - Hi again Pat! I almost missed your post! <b>>>... but in the Hi again Pat! I almost missed your post!>>... but in the West and according to most authorities, the whole idea is to not mix up the lower and upper layers.< [heh heh] Well... I've never been accused of being one to follow the consensus. :>) Your point is well taken, and I emphasize to those following along that this "double digging" should only be applied to areas of heavy clay soil with very poor drainage. In our Texas Blackland Prairie and Western Cross Timbers geographic zones, we call it black or brown "gumbo." (When I lived in the upper Midwest, we called it "brown goop." And in the Southeast, we called it "black bottom land.") Let me take a minute here to address those "lurking" in the background who may not be familiar with what Pat and I are "chatting" about. Generally speaking, "normal soil" is divided into five predominate vertical layers, called "horizons." The topmost layer, called the "O horizon," is composed of organic materials, leaf litter, etc. from plants and animals, and found chiefly in forested areas. The next four horizons are lettered A through D. The A horizon is the most important because it lies at or near the soil's surface where plant roots will feed, contains all the aerobic microbial activity necessary for the breakdown of organic materials into humus and minerals into usable ions, and is home for most of the soluble precipitates or minerals to be taken in by the plants. The B horizon is the compacted subsoil and lies just beneath the A horizon. The C horizon is the rocky subsoil composed of aggregate that has yet to coalesce into bedrock, called the D horizon. The argument for not flipping the two soil levels when double digging is based, as I understand it, on two important reasons: First, by putting the upper 12 in. (30 cm) of soil in the bottom, one moves the microbial activity to an area where they will have a difficult time surviving and gas exchanges will have a hard time occurring. By subsequently placing the lower 12 in. of soil, presumably devoid of microbial activity, on the top, one delays The Nitrogen Cycle (et al.) until new microbial activity can begin. Second, in some arid areas of the West, Southwest and Midwest, where the A horizon is naturally thin or has been overworked through continuous agriculture and the overuse of synthetic fertilizers, the turning of the A horizon may bring the B horizon into the region of cultivation. This is normally not a good idea because the B horizon contains the most iron, aluminum oxides and silicate clays, and therefore high in minerals which are not easily leached. It may also be high in calcium carbonates and other salts which may have a profound effect on soil chemistry and therefore plant vigor and wellbeing. My argument for flipping the first 2 ft. (60 cm)of heavy, tight clay soils is based on my experience and observation after digging in and performing tests on these soils over the years. I have found that in these soils, the B horizon seldom exists. The A horizon is usually merged into two subdivisions, called A1 and A2, and they transition directly into the C horizon or sometimes directly to the bedrock. In these soils, the A1 and A2 subdivisions are devoid of aerobic activity, have little or no humus, already contain excessive calcium carbonates, and if any earthworms are present, they are usually well below the surface in small populations where residual moisture may occur. By flipping the top 20 - 24 in. of of these tight soils, adding soil loosening agents, organic materials and sometimes microbial inoculants and stimulants, my experience has been that soil macroorganism activity appears sooner, micorrhizal fungi appear quicker so plants suffer less transplant shock, and the plants exhibit less of what I call "zonal chlorotic conditions" (eg., chlorotic conditions on the leaves of one stem or cane, while the remainder of the shrub appears normal), presumably because of more equally distributed microbial activity. Sorry for the long reply, Pat. Your comments are good ones, and I appreciate them. I just love to get into the "dirty" details of gardening. :>) MarkW>Ft. Worth, TX/Zn 7b, Rose Garden -- posted by Mark_Whitelaw » PatP_2 - Pat Patterson As I suspected you have really different soil tha Pat PattersonAs I suspected you have really different soil than we. (I'll take mine anytime!) Still what you doing is not techically double digging so much as doing the equivalent of chisel plowing for awful stuff all the way down. Sorry to be such a word purist. One of my many vices. 8-). You are basically doing what we do for trees in awful soil, We deeply dig and amend an area of at least 10x10' in order to give the new tree growing room. What we do not want to do is just amend that planting hole. Do the same for roses. When we put them in (clay over sandstone), we deep plowed at 10 foot by 100 foot area and amended that. That was over 20 years ago and I have never regretted all that work as the plants there are ecstatic with just a heavy yearly topdressing of compost and manure. Thanks for all your sharing. Pat in Noti, OR -- posted by PatP_2 » D_Austin - soil preparation question Mark: I like your 'natural' approach to soil preparation and fertilisation. I am a beginning rose gardener.Had a couple of questions: -I live in clayey N Georgia. Is it OK if I simply replaced 2-3cu ft of the clay with top soil/Nature's helper or similar sold in the garden stores mixed with blood meal/limestone etc., rather than amending the clay. - Apart from the biannual tonic you mention in an another article, you talked about a monthly feeding. What do suggest this feeding should be? I am planning to plant 2 Griffith Buck roses(Serendipity and Silver Shadow), a Gruss en Aachen and a Zephirine Drouhin. Thanks-David -- posted by D_Austin » Mark_Whitelaw - Clay soil preparation Hi David! Welcome to Rose Garden!With a name as famous to rosedom as yours, it's no wonder you're growing roses! Glad you stopped in for a visit. Your questions are good ones, and subjects we haven't touched on for a while. Let's take each of them and explore the possibilities. Is it OK if I simply relaced 2 - 3 cu. ft. of the clay with top soil... rather than amend the clay. It would be okay if your clay soil was reasonably loose. But I don't recommend the procedure for a number of reasons. First, 2 - 3 cu. ft. of soil isn't very much soil - essentially, only about a small wheel barrow full. If your soil is clay-based (as are many of the soils here in my part of the country), you will need to replace the soil for 2 - 3 ft. down and for the width and length of your rose beds. Since you are planting four good-sized roses, this could mean a cubic yard of soil for each rose... or roughly 108 cubic feet of soil! That's a lot of bags of soil! Another problem with simply removing the existing soil and importing a soil blend is that you may be creating a "bowl effect" from which water cannot drain. Furthermore, because the top soil may quickly appear dry, you may be tempted to irrigate more and exacerbate the problem. Planting roses into well-draining soil which is placed inside a poor-draining hole (the bottom and sides of which are composed of compacted clay soil) will not solve your drainage problem. It would be as if you were planting a house plant in a container without a drainage hole in the bottom... like a water bucket. Water will drain through the good "top soil" very well, but will collect in the bottom of the hole, possibly taking hours or even days to drain away. Still another problem can arise. Since the top soil drains well, the soil and roots near the surface will dry while the roots and soil in the bottom of the bed will remain wet and displace the air in the soil, eventually fouling the soil and killing the plant. If your clay-based soil is extremely heavy, I would recommend you either dig out the bed and install a drainage system, or elevate the bed. Of these two options, I recommend the first - the drainage system. If you elect the in-ground drainage system method, you will need to dig out the soil for about 32 in. and install perforated drainage pipe or several inches of coarse (1 in.) river rock in the bottom of the bed. You can then fill in with either an amended mix of your native soil or an imported soil blend. The native soil, amended to include those elements missing from your soil test, is preferred. Amended native soil will allow your roses to adapt to their microenvironment more quickly than using an imported soil blend. Otherwise, when the roots grow beyond the imported soil and extend into the native soil, their growing conditions will change. Many of my clients who opted for the imported soil method have had roses do very well for the first few years, only to have the roses undergo stressful conditions as the roots penetrated into the native soil. Going back to your bed options, if you opt to raise your rose bed, you will want to loosen the soil underneath the elevated bed's location for the first foot or so below the ground level. Then, after creating your elevated bed, you can either use amended native soil or bring in imported bedding soil. Again, I recommend the amended native soil option. So, you ask, how do you determine if your clay soil will suitably drain for growing roses? The answer is to perform a "percolation test" of your intended bed's location. The American Rose Society suggests a method of performing this test. (They "borrowed" the method from the Ortho Company - with their permission, of course.) Use a 2 - 3 lb. coffee can (or a can of similar size), the top and bottom of which have been removed. Push the edge of the can into the soil to a depth of about 1 in., and fill the can with water. Measure the length of time it takes for the can to completely drain of water. If it takes more than an hour for the water to drain, you must take appropriate steps to improve the drainage of the soil. Once you have amended the soil, you must also take a measurement to see if the soil will retain moisture sufficient to do your roses any good. (For some folks who live in sandy soil, this can be a real problem! Water drains so fast, the roots don't have a chance to take it up!) Again, thanks to the Ortho Company and the ARS, there is another test you can perform called a "water retention test." Fill a 1 quart (about 8 in.) plant container (the bottom of which should have drainage holes) with your amended soil (or soil blend). Saturate the soil mix with one quart of water and elevate it above a clear glass container or jar (like a Mason jar used in canning fruits and vegetables). A funnel placed in the mouth of the container or jar will make this task more easily accomplished. Measure the amount of water that drains from the saturated pot after 15 minutes, 30 minutes, and again after one hour. Knowing that you poured in one quart of water (which equates to "100% drainage"), and knowing how much water drains in a quarter hour, half hour and whole hour gives you a "water retention factor." What you're looking for is a range of 50% - 60% water retention after one hour. If your reach the 50% factor in a quarter hour or half hour, you must amend your soil mix to retain more water. (In your case, add more native clay soil.) If you have less than 50% drainage after one hour, you must amend your soil blend to improve the drainage... add more soil loosening agents like aged pecan shells, gravel, etc. But, under no circumstances, should you add "brick" sand to your bedding mix as a loosening agent. This eventually settles to the bottom of your planting bed, creates a hard pan, and reduces drainage. Apart from the tonic you mention in another article... What do you suggest this [monthly] feeding should be? Because of our rose growing conditions here in Texas, I prefer to feed my roses with a semi-monthly application of fish emulsion and seaweed. The product I use is Bio-Form™ although there are several products available which have a preblended formulation of these ingredients. When the heat of our summer begins (usually around the end of June or beginning of July), I discontinue feeding until my late summer light pruning and fertilization in preparation for fall flush. This usually occurs around the end of August. Hope that helps a bit. Sorry for the length of this response, but your questions were good ones and deserved a suitable reply. Have a great gardening day, and come back often! -- posted by Mark_Whitelaw » WilliamG - Compacting of Soil in Potted Roses I went in and looked at the article and reviewed the various information regarding preparing good rose soil. My question is that I have my roses planted in pots from last year and I want to know what I should do to scratch around or aeriate (sic) the soil as spring approaches? I have already put my "Spring Tonic" on the roses and have been watering regularly (when it hasn't been raining.What other preparations do I need to make for the Spring growing season? Should I do the same thing around the roses established in garden beds? -- posted by WilliamG » Mark_Whitelaw - Aerating the soil Hi William! WB!You can aerate the soil in your beds with a garden fork. For your containered roses, try using a skewer or small garden cultivator. In both cases, just press the tines into the soil using caution to not sever major roots. As far as other pre-bloom (pre-spring) procedures: pruning properly, adding an organic soil supplement (dependent on a soil test evaluation), cleaning up debris from the winter, remulching, and keeping the roots moist is all that is required. As leaves begin to appear (as is probably the case in your location), begin your preventative fungal disease control. -- posted by Mark_Whitelaw » NickHudd - Adding nitrogen Hi everyone. I've been away for a few days in Cambridge and York (and getting into pubs, Mark, with the other rose-growing Mark - Farrington - big grin).Adding nitrogen to undecomposed organic matter I always use ammonium sulphate to get the quickest possible action. The organic matter may take nitrogen briefly from the soil, so the faster the action begins the better, I think -- posted by NickHudd » Mark_Whitelaw - Good tip! Good tip, Nick!How's Mark F doing these days? -- posted by Mark_Whitelaw » NickHudd - Cambridge Hi MarkI was with Mark F. last week in a pub outside Cambridge. We tend to meet a couple of times a year, this time to swap a video and for him to return my copy of La Rose de France - book about gallicas. It's a splendid book, in French, and outlines the history and details of the gallicas much more than any other source I have seen. It is a vast treasury of information about roses I had never heard of at all. It is also, I have to say, a magnificent book itself, with superb illustrations and an excellent quality of production all round. Mark again tried his hard sell of the Cambridge Botanic Garden, which I have never seen, and which my wife nags me about[grin]. I must get there sometime (while he and I were pubbing, my wife and son were in the adjacent Air Museum, which includes the UK's American Air Musuem) -- posted by NickHudd « Previous 1 2 Next » Please follow the guidelines set forth in the Suite101 Posting Etiquette when adding to the discussion. |
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