Raised bed gardening is an excellent way to garden in a small space. The quality of soil for raised beds gives gardeners one reason they produce bumper crops.
If you experience trouble stooping, bending and kneeling, raised bed gardens allow for easy care. You can set up your raised bed garden at a height most comfortable for you.
With complete control over the soil, you can mix the soil you want and put it in place for the best results.
Let’s be clear…
No specific combination of ingredients will make the perfect all around raised garden soil. What you put into your soil depends very much upon what you plan to plant and your local climate.
Various plants require different pH levels. For example, blueberries need a more acidic soil.
Additionally, gear the soil texture toward your local weather conditions. For example if you live in a very arid and dry climate, you will want a soil mix that will retain moisture with good capillary action.
On the other hand, if you live in a very rainy and damp area you will want to create soil for a raised garden bed allowing for good drainage.
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Soil Mixture For Raised Beds Begins With A Good Basic Soil Mix
One good way to start “building” out fertile soil… begins by making a 50-50 mix of high quality compost and screened topsoil.
When you blend the compost and screened topsoil together thoroughly, you will have a nice basic soil mixture you can amend to suit your specific climate and plant needs.
For a more quickly draining blend of compost, create a three-part mix. For this coarse mixture, combine equal parts of:
- Horticultural Coarse Vermiculite
- Blended Compost
- Canadian Sphagnum Peat Moss
As with the 50-50 mix, combine the horticultural vermiculite, compost, and peat moss thoroughly for best results.
Coco coir makes a great alternative for peat. Additionally, to get a wide variety of plant nutrients for your organic garden source compost from at least five different places.
Why Not Just Buy Compost?
If you rely only on bagged compost from the garden center, you’re likely to get a scarcity of organic nutrients. There is really no reason to purchase compost. It is easy to make your own compost at home.
A well-seasoned compost rich with organic matter, made from yard and garden clippings and kitchen scraps provides a wealth of nutrients for organic gardening.
If you also keep chickens, equines, rabbits and/or goats you have an excellent source of rich and nourishing compost. If you do not personally keep any livestock, you should look for a local organic farm or gardeners supply where you can purchase some natural compost.
Raised Garden Bed Soil Does Not Have To Be Deep
When you have created this kind of high quality raised bed gardening mix, you don’t need to spread it very thickly. This highly nourishing fertile mixture will support a wide variety of plants even if it is only six inches deep.
Be sure to line the bottom of your raised bed with thick layers of cardboard (sheet mulching) and/or newspaper or landscaping fabric to prevent plant roots from contacting native soil and to prevent weeds from growing up into your rich soil.
When Should You Amend Soil Used In Your Raised Bed Garden?
Early in the spring each year, till your raised bed garden soil and replenish it. Remember that friable garden soil is airy, soft and light.
You should be able to poke your finger into your soil easily all the way up to your topmost knuckle. If you find your soil is hard and unyielding, take steps to till it, amend it and lighten it.
Experts recommend to till the native soil first before starting to fill the raised beds.
How To Amend Soil Mixture For Raised Beds
Both the 50-50 mix and the three-part mix provide basic building blocks for good soil in the garden. Once you have this in place, you can tweak and amend the soil to suit your particular plant choices.
One good addition to well-balanced garden soils is organic, slow-release organic fertilizer. Working this into the soil one or two times a year (e.g. early in the spring and/or late in the fall) will help boost the nutritional value of your soil.
After application, apply a generous layer of mulch or compost to hold the nutrients and moisture into the soil.
A few other good specialty amendments include:
- Shredded bark, wood chips and/or sawdust breaks down slowly and helps improve the structure of your soil.
- Both used tea bags and grounds and composting coffee grinds also provide all of the NPK components and are an excellent addition to your compost heap.
- Seaweed provides a good balance of nitrogen, potassium and calcium; however it is especially rich in potassium.
- Alfalfa meal is an excellent source of nitrogen, and it also provides some micronutrients, potassium and phosphorus.
- Sulfur helps increase the acidity of your soil and makes it easier for your plants to absorb calcium from the soil.
- Dolomite lime helps increase the alkalinity of the soil and adds a good dose of magnesium and calcium.
- Aged manure (a minimum of six months) provides a wealth of minerals and of nitrogen.
- Wood ash in garden soils decrease the acidity of the soil and add a variety of nutrients including potassium.
- You may wish to use perlite instead of vermiculite because perlite holds moisture better.
- Green sand releases micronutrients and potassium in a slow released fashion.
- Rock phosphate releases micronutrients and phosphorus in a slow manner.
- Bone meal provides some nitrogen and a good dose of phosphorus.
- Gypsum is a good addition to make a well-drained soil.
- Soybean meal releases nitrogen in a slow and steady manner.
- Epsom salts provide a nice dose provide a nice dose of sulfur and magnesium.
- Blood meal provides a healthy dose of nitrogen.
- Learn More About Using Organic Soil Amendments to Improve Your Soil
Create Soil For Your Raised Garden Bed To Suit Your Purpose
The texture of your garden soil should be in line with your goals. For example, if you are sowing seeds directly into your bed, you will want to have a finer texture of soil. Luckily you don’t have to change out all of the soil in the bed to do this.
Begin with your basic 50-50 or three-part mix and then top it off with a finer textured soil. A good soil for seed starting should be spongy, moist and rich. You can accomplish this by creating a combination of finely sifted, blended compost and peat moss as your seed starting medium.
Mulch Is Very Important!
Remember, with fairly shallow soil, garden mulch plays an important role. It helps hold in moisture and protects the soil from damaging rays of the sun. It also helps prevent invasion by weeds.
Once your seedlings have started, thin them out to allow the hardiest to take hold. Mulch around them to hold nutrients and moisture into the soil to help them thrive.
You may be surprised to know that modern gardeners believe that a couple of inches of pure compost make the best mulch. It performs all of the protective and moisture holding functions of bark mulch and adds nourishment to the soil.
The Right Soil Produces Bumper Crops!
Raise bed gardening is a great choice for small spaces. Properly maintained raised gardens can produce four times the amount of crops or vegetables as a traditional garden patch using compost alone.
This is great for home vegetable growers with very small yards or even patio and balcony type garden settings. When you put forth the effort to create light, airy, highly nutritious soil mix for your raised-bed gardening project, you can expect to enjoy abundant success.