I was wondering what soil to use in raised beds inside our new greenhouse Most of our soil on our farm is heavy clay (gumbo) We do have some pretty good cattle mulch piles that have been around for several years. I would be willing to purchase a commercial soil if I knew what to look for. Our greenhouse will be a permanent triple walled polycarbonate style, so we want to make the right soil choice. Is simply buying a commercial "garden soil" or "top soil" good enough or should I add in some of our own cattle compost ? Thank you for your time
Lyman County South Dakota
There are many ideas for the "right" soil mix. You did not indicate if you have your gumbo soil as the base of your bed or if you have a liner. I will give you ideas for how to work with your soil and without.
If you have the ground as your base you may want to double dig. To double dig prior to establishing a raised bed, remove all the soil from the bed one spade's depth. Dig the next layer down, leaving the soil in place. Add soil to the bed and thoroughly mix the layers. Double digging permits deeper rooting by plants growing in the bed. Instead of your soil you may want a commercial soil (see below).
The addition of organic matter to any soil will improve its physical and chemical makeup. Peat moss, compost and decomposed manures are good sources of organic matter. To take full advantage of the deep rooting potential with raised beds, work up the base soil by rototilling or hand-digging before bringing in additional soil. Avoid hauling in new layers of soil without mixing them into existing soil. Distinct layers of soil create barriers through which water will not readily penetrate and roots will not easily grow.
If you just want to add soil some suggestions are below. I hope this is helpful. Happy Gardening!
"Soil": Use bagged composted cow manure or compost. You can also mix together potting "soil" and compost but this is more expensive and not better for growing your plants. If you are creating a large garden, you can buy compost in bulk to save money. Hint: Avoid using top soil or earth. They can have nematodes, soil-borne plant pathogens, and often does not drain well. Purchased garden soil is usually not uniform. The optimum soil mix for raised beds is a 1:1:1 ratio of sand, compost and garden loam. The problem is that you may be introducing incredible amounts of weed seeds and disease-causing organisms if the soil has not been treated to eliminate weeds and disease organisms. Most garden centers sell a garden blend of soilless soil or media that works well for vegetables. Soil should be dark and comprised of decomposed materials. Try to choose a soil that isn’t primarily large bark pieces. Too much bark ties up nutrients and drains too quickly. When buying soil or planting media, ask the seller for a copy of the soil analysis. Make sure the soil has a pH of 5.5 to 7.0. This is the perfect range for most vegetable crops. .