Flowerbed Soil Preperation
The key to gardening success, whether you are growing veggies, flowers or shrubs, starts with the quality of your soil. Without the foundation of a strong root system your expectations of the plants you grow will not be met. We will try to give you a simple step by step process with explanations included.
Define the Shape
The first thing to start a planting bed is to define it's shape. For beds with curves a great way to do this is to lay a garden hose along the intended outline of the bed. You can adjust easily, stand back and see if you like it. If not, readjust until the desired shape is found.
Trench
When you raise a bed 6" it will need to gradually slope down to grade (usually lawn) unless you have a physical barrier like landscape timbers or rock, to hold the soil in place. Take a shovel and make a trench along your garden hose about 4-5" deep. Throw the soil you dig into the flowerbed.
Add Soil Amendments
Soil amendments are materials that will make the flowerbed loose, rich, raised and well drained. Topsoil used exclusively is not recommended to condition a flowerbed. It will pack down hard and not allow for good drainage. Shredded mulch is also not a great material to condition and work into a flowerbed.
There are many amendments that you can incorporate into your existing soil to prepare a vegetable garden, a bed for flowers or shrubs and trees. For heavy clay soils a great material to use is expanded shale. Nothing breaks up clay soils and keeps it that way better than expanded shale. 3 inches of expanded shale and 3 inches of a high quality compost mixed into your existing soil will produce a great media to grow most trees, shrubs and flowers.
If you have a sandy loam soil you do not need expanded shale. What you will need is organic matter that will help retain some moisture and nutrients.
If you have large flowerbeds and you plan to buy bulk soil you have several choices. Most soil yards have a landscapers mix that will contain sand, topsoil and a fine organic matter like composted bark. They will likely have an azalea or a rose mix. Any of these mixes will provide a good foundation to grow most plants. None of these mixes has expanded shale so if you do have heavy clay an addition of the shale will be of great benefit.
If you are planning to use bagged products to create your flowerbed you will also have many options. Rose soil and azalea soils are complete
mixes and all you need to do is add, till and rake smooth.
Many other soil amendments can be added to the bed if you chose to. Peat moss is a great additive to help acidify the flowerbed and retain moisture. Composted manure will add valuable nutrients and increase the biological activity of the soil. Rice hull compost, leaf mold compost and cotton burr compost are wonderful additives and can be used exclusively to create a quality planting bed.
Whichever materials or soils you decide to use add at least 4-6 inches and thoroughly till this into the existing soil to a depth of 12 inches. If you need to figure out how much soil you need please use our soil calculator .
Remove clods and rake smooth
You will need to remove small tree root pieces, clay chunks and any trash that you dig up. Rake smooth and be sure to never cover up the weep holes around your brick home. If you do cover them up you will see water in your home after a good rain.
OPTIONS
Even though you can plant at this point there are quite a few extra things you can do if you want to. First of all, you can check the pH of the planting bed and if it needs an adjustment now is a great time to do it. For acid lovers like, azaleas, gardenias, camellias and magnolias we recommend a pH of 5.5-5.8. For most other plantings we recommend 6-6.5. Sulphur increases the acidity and lime increases the alkalinity.
You can also incorporate fertilizer into the soil when tilling to increase the soil fertility. Be careful, more fertilizer than the directions say is not usually better!
Gypsum can be added to chemically help break up clay soils.
Bull rock can be added to a flowerbed where water drops from the roof or where you have natural runoff. This will help reduce erosion in your flowerbed.
Adding mycorrhizial fungus can be a great benefit. They are beneficial microbes that inhabit healthy soils. You don't have to wait to increase their populations. Add them when the planting bed is prepared.
You can install a weed fabric that acts as a physical barrier to prevent most of the weeds that will pop up. Whenever you turn soil and expose this new soil to sunlight, oxygen and moisture the weeds seeds that are present will try to germinate. This can quickly become an instant weed problem.
After planting, a weed seed preventer (pre-emergent herbicide) can be applied that will prevent most of those exposed weed seeds from popping up. You would use this in place of a weed barrier.
After the planting bed is made and the planting is finished it is time to mulch. Do not mulch before you plant. Mulching should be the final touch to creating a beautiful new landscape.