Now is a good time to build a new rose bed. The goal is to get the bed in several weeks before you plant your roses so everything has a chance to settle in and mellow out.
Because most potted roses will be planted in March or April (depending on when the local nurseries receive their stock), now is the time to get started.
Our goal is to make a raised bed because in Houston our natural soil is gumbo clay. The microscopic particles that make up clay soils are rich in minerals, but they are so close together that air and water have a hard time moving about. And roses need both air and water in the soil.
Don’t build a bathtub. You might think that digging a hole, throwing out the gumbo clay and putting in good loam would be doing your roses a favor. But what you would really be doing is putting the plant in a bathtub. The rose soil would be surrounded by clay, and when it rained the water would stay in the bowl you dug and drown the rose. Another approach is needed.
Raised beds. Roses don’t like wet feet. They want well-drained soil. Because digging down won’t give them what they need, we build up. The HRS recommends that your new rose bed be a raised bed between eight and ten inches high.
Nature’s Way Rose Soil Blend is perfect for such beds. It is available by the bag or by the truckload. The HRS helped with the formulation of this excellent blend. On the other hand, if you are on a tight budget, you can follow the formula of 1/3 soil, 1/3 coarse builder’s sand, and 1/3 mulch (or compost). Texas A & M has had great results by adding expanded shale to the rose soil blend. That is what I do. I advocate adding 25% expanded shale to the basic rose soil. I use a wheelbarrow to mix the ingredients. One shovel full of soil, one of sand, one of mulch and one of expanded shale. Mix and repeat until the wheelbarrow is full. Or, if I am using the Nature’s Way Rose Soil Blend, I put in three shovels full of their blend and one shovel full of expanded shale and mix thoroughly and apply to the rose bed.
Expanded shale is sedimentary rock that is crushed and heated to over 3,000° F. It expands like popcorn into a rock that is lightweight, hard and very porous. All those pores are what make it such an excellent soil amendment for roses. It is much better than sand for allowing the passage of both water and air through the soil. It does not change the pH of the soil. Also, because it does not decompose, it is a one-time addition to your rose soil.
There are several benefits in making a raised bed. First, you will be providing your roses with ideal drainage. When water drains off at the proper rate, there is both water and air for the roots and soil organisms. As water is taken up by the feeder roots or passes down by gravity, air goes into the soil and occupies the empty spaces. Earthworms can also bring air into the soil with their digging. Air in the soil is essential for healthy roses, and soil texture is the key to getting the air down where it is needed. There are other advantages to raised beds. Every inch your beds are raised above the native soil level is an inch of bending you can avoid for your knees and back. Also, a raised bed is aesthetically more pleasing to look at. It marks the area you have set aside for beauty. And because no one should be walking on your raised bed, soil compaction is eliminated.
Let newspapers do the work. If the place where you intend to put your new rose bed is currently covered in grass, there is no need to dig that grass up. Save some work. Lay eight to ten sheets of newspaper on the ground where the bed will be. Be generous. Make sure the pages overlap each other. If there is a wind blowing, use rocks to hold the newspapers down. Then add your rose soil blend on top of the newspaper. The paper will kill the grass and eventually decompose.
Where to build your beds. You can’t always build a new bed in the ideal location, but below are some of the
factors to consider:
1) Keep away from trees. Their roots will head for all the amendments you add to your rose beds.Trees
are greedy eaters.
2) Trees also produce one of the main enemies of roses: shade. Roses like full sun. All day long sun.
Make sure your trees don’t shade your planned rose bed location. And if a deciduous tree is nearby,
don’t be fooled by the seasonal lack of leaves. When spring comes and the tree leafs out, the bed that
is sunny in January may be in the shade in April. Plan ahead.
3) If your planned rose bed is near the house or garage, pay attention to the eaves. Rain may produce a
waterfall right on your new roses. Move the bed or add gutters.
4) Think about the width of the bed. You can plant two rows of roses if you have the room and can
access both sides of the bed. If the bed is up against a fence, you would be wise to only have one row
of plants. And never plant three rows of roses, even if your can access both sides of the bed. Tending
that middle row is guaranteed to give you a close encounter with thorns and the chance to practice
words you might not use in public.
5) Don’t forget to allow space for paths. My romantic vision is of a couple strolling through the garden,
hand in hand, smelling the roses. That means at least a four foot wide path and five feet would even
be better. Crowding someone into a three foot path guarantees both unending diligence in pruning
wayward branches and single file visitors.
6) Put the bed where you can see it. If your roses are where you can see them, you will notice problems
sooner and will also appreciate their beauty more often. It really is true with roses that out of sight is
out of mind.
Edges. It is not impossible to make a rose bed without some material to hold in the soil. But unless you have some kind of border material, you will have problems maintaining the proper height of your raised bed. And you will be forever plagued with invasions of St. Augustine grass and the dreaded Bermuda. Thus, almost all raised beds have retaining walls of some kind.
Landscape timbers are very common. They make crisp right angles in a formal garden. With some planning, curves can be made. Use a tree saw to cut the timbers to length. Still, environmental regulations have made it difficult to find pressure treated lumber that will actually resist rotting when in contact with soil. Plan on replacing them every so often.
Cement blocks are easy to put down and Windsor Stones are colored blocks that have wedge shapes that allow you to easily make gentle curves. Cement tends to stain with repeated watering, so plan on dealing with mold from time to time.
Pavers or regular house bricks are classy. They can be placed upright on end (soldiers) or length-wise on their sides (sailors). Curves are doable, especially if you use half bricks to make the bends. They give a formal look to the garden.
Some people use metal edging to make their beds. The problem is that the metal inevitably rusts and the edging is not really tall enough for the height of the raised beds we need in Houston. Plastic edging avoids the rust problem, but it is hard to find over six inches in height.
Personally, I like dry stacking stones for my beds. Although there is an initial expense, rocks do not rot. And curved beds are very easy. They give a natural look to the garden. Dry stacking makes changes easy, and you don’t have to bother with mortar.
Don’t forget to add an irrigation system to your new bed. Roses need one to two inches of rain a week. A raised bed prevents roses from growing in standing water, but that good drainage demands regular supplements of water.
Lastly, be sure and finish off your beds by adding three inches of mulch on top of the soil. Your roses will thank you for it and visitors to you garden will marvel at the beautiful addition to your garden.
This article originally appeared in the February, 2015, issue of The Rose Ette, the newsletter of the Houston Rose Society.
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