Five Rules Of Thumb For Preparing Your Garden Bed

"Make your bed!" is one of those statements that we each had to have heard a million times as kids. As gardeners though, this simple phrase has a different meaning. Make your bed is all about preparing the soil for planting. Every gardener gets excited by the thought of finally getting their hands in the soil and planting out their newest plant acquisitions. The joy of finally getting to see the garden come together in spring is certainly a fun experience. However, the key to garden success starts before the first plant even sees the garden.

The roots of a plant are the foundation on which that plant thrives. Good roots will generally mean that you have a happy, healthy plant that can survive the rigors of spring and summer with aplomb. A poor root system means your plants cannot grow to their full potential and leaves them vulnerable to damage from insects and disease. The most important factor for good roots is good soil preparation. If you are a beginning gardener, properly preparing your soil can be daunting. However, there are some simple steps that you can take to get your beds ready to be planted.

There are three basic types of beds you might be preparing. The first type is a brand new bed that has never been planted before. The second type is an empty bed that has been planted before. The third type is a bed with existing perennials, bulbs, and/or shrubs.

When preparing a brand new bed the first step is to kill the existing vegetation. If this is woody material you will need pruners (265-5950) or perhaps even a saw. If the existing weeds are herbaceous plants, things like grass and chickweed, you will have an easier time. The best way to begin to prep this type of bed is to define the outline of the bed in the fall. It can sometimes be helpful to use a garden hose (274-1035) to determine the outline.

Once you know the shape and size of the bed, cover the soil and plant material with several layers of newspaper (a good 5 to 6 sheets should be sufficient) and then cover the newspaper with a good thick layer of compost, 2 to 3 inches would be great. Leave the bed alone until spring. Over the fall and winter the newspapers will block out all light which will kill the vegetation. The newspapers will also decompose over several months and come spring you will have a nice layer of compost that you can turn over into the soil. This method is completely organic and will help improve your soil while you kill existing vegetation.

If it is already spring and you want to plant your bed soon, use an herbicide, such as Roundup, to kill the existing vegetation. Be sure to read the label for instructions, below 50 F Roundup is not effective.It works best when weeds are actively growing. Roundup decomposes in the soil and does not contaminate the environment. It also works on both annual and perennial weeds, where the newspaper route will only control annual weeds.

Once the existing vegetation is dead use a tiller, spade/shovel or garden fork to turn the bed over. With a brand new bed it may be difficult to get your tiller to break into the soil so turning the bed over first with a spade or shovel (265-4114) may be best. When working the soil you want the soil to be damp but not wet. If the soil is too wet it will clump when you turn it over. If the soil is too dry it will be very difficult to dig and harmful to the soil. If you turn over a spade full of soil it should break apart and look moist without sticking to your tools or dripping water. A tiller will often turn the soil to a depth of 6 to 8 inches. It is good to get down at least 12 inches (the depth of a space or shovel) when turning over a bed, another point in favor of the shovel. If you are really motivated turning over the soil to a depth of 18 inches is even better, although it is a lot of work. This is often called double digging.

Once you have turned over the soil spread a layer of organic matter or compost 2 to 3 inches thick over the bed and then turn the soil over again to mix the compost into the soil. Adding compost will improve the soil by adding nutrition and improve soil structure. Avoid extremely fine compost or bagged amendments with a sand-like consistency as they tend to break down too quickly. You want something that has both large (1") chunks as well as smaller particles. Then rake the surface of the soil to level the soil and create a nice soil bed.

Turning over the soil will expose weed seeds that were previously buried to light, causing germination of these seeds. You can control the germination of these seeds by applying a thick mulch like pine needles or bark products over the bed or you can treat your bed with a weed and feed product to help deter germination of weed seeds. If you do treat with weed and feed be sure to read the directions and apply correctly, some weed and feed products can damage roots below the soil if applied incorrectly.

Also, do not direct sow flower or vegetable seeds into the soil when using a weed and feed product as they will not germinate. Weed and feed products kill all germinating seeds not just the weed seeds. If you use a weed and feed product you will want to install plants already growing in pots or packs to fill your bed the first spring. By fall the chemicals should have broken down and you will be able to direct seed if you want. After you plant the bed you may still want to add a layer of compost to the top of the soil. A layer of mulch or compost on the top of the soil will help keep weeds from growing making for a neater look overall, and will also help maintain moisture in the soil.

    Rules of Thumb for Brand New Beds:

  1. Work the soil when it is moist but not wet.

  2. Turn the soil over to a depth of at least 12 inches.

  3. Add 2-3 inches of compost and turn it into the bed.

  4. Either cover the bed with a thick (3-4") layer of mulch or use a weed and feed to help keep weed seeds from germinating.

  5. Top dress with another layer of compost to keep down weeds and preserve moisture.

The second type of bed is an existing bed that has nothing in it, in other words you are replanting the same area you used last year. With this type of bed you can treat it similarly to the brand new bed but it shouldn't be necessary to layer the newspapers to kill existing vegetation. In either fall or spring or in both seasons put a 2 to 3 inch layer of compost on the bed and then turn the compost into the soil. The single best thing you can do for your soil is to consistently add organic matter. This will enrich the soil and help you grow better plants.

Once again you only want to work the soil when it is moist not wet or dry. To check your soil moisture content pick up a handful of soil and squeeze it. If you squeeze out water the soil is too wet to work. If the soil stays in a ball in your hand and then breaks apart when tapped it is perfect, if the soil is too dry to form a ball it is too dry. If you work soil when it is too wet you will cause it to clump and become compacted. If you work soil when it is too dry you harm the soil structure. Working soil when it is moist will help maintain good air porosity and soil structure.

After you add the compost layer you will want to turn the compost into the soil. As before, you can use a tiller, shovel or garden fork to do this. I prefer to use a shovel so I can get at least 12 inches deep. Double digging will again be the optimum but any incorporation of organic matter over will be beneficial. After turning this compost into the soil you may want to put another layer on top of the soil to act as mulch. If you add organic matter in the fall it isn't necessary to add more in the spring. However, if you have poor soil adding compost twice a year can help improve the soil more quickly. Remember that this organic matter gets used up each year and needs to be replenished to keep plants performing their best.

    Rules of Thumb for Existing but Empty Beds:

  1. Add 2-3 inches of compost and turn it into the bed.

  2. Work the soil when it is moist but not wet.

  3. Turn the soil over to a depth of at least 12 inches.

  4. Top dress with another layer of compost to keep down weeds and preserve moisture.

The third type of bed is one that already contains some perennials, bulbs and/or shrubs. These beds can be a bit trickier. You can't simply broadcast a thick layer of compost and then turn it under. You will need to be careful when working around the established plants that you don't harm their roots. You do still want to add organic matter. Add a couple inches of compost around existing plants, work this into the top layer of soil a bit if possible but do not dig deep enough to harm the roots. Do not allow the compost to come into contact with the stems of the plants as this can promote disease. Even left mostly on top of the soil the compost will break down over time releasing valuable nutrients into the soil while preserving moisture and protecting the surface of the soil.

Established beds will often have open areas where plants have died or where annuals are added each spring. In these areas go ahead and turn over the soil to incorporate the organic matter into the underlying soil and then plant.

    Rules of Thumb for Existing Planted Beds:

  1. Add 2-3 inches of compost and work it into the top layer of soil if possible

  2. Work the soil when it is moist but not wet.

  3. Do not allow compost to come into contact with plant stems.

  4. Top dress with another layer of compost to keep down weeds and preserve moisture.

Preparing the soil in your beds doesn't have to be difficult, although it is great exercise. Adding organic matter is the one thing that all soils can benefit from whether your soil is sandy or clay based.

- Proven Winners