by Gary Pilarchik (The Rusted Gardener)
Do not get fooled into thinking you need to buy expensive container/potting mixes for your container vegetable or flower gardens. There is nothing magical about the base ingredients they use that you can't buy separately, mix and make something as good if not better.
Why make your own container mixes? It will save you a ton of money that you can use in your garden in other ways and you can tweak your recipe, based on the needs of your garden. For instance, high summer heat... add more peat moss, coco coir or water retaining organic matter. And perhaps the best reason, you know what is going into your mixes!
First point, compost is king. Compost you make from leaves, grass cuttings and food scraps is probably the best container soil out there. However, most of us can't make enough to meet our needs or don't have the space to make our own. Second point, the bags labelled 'Potting Mix' are typically made up of 5 things; peat moss, fine wood chips, soil perlite and fertilizer. Sometimes they, but rarely, will contain vermiculite. When you read, "special formulation for moisture control" that means peat moss 99/100 times.
The video shows you products you can buy (with prices) to blend you own container mixes at a fraction of the cost compared to buying straight bagged potting mixes. You can also use this for your raised beds and again, you don't have to pay a lot for bags that say "formulated for your raised beds." Those products work and are convenient if you don't have time to make your own.
The basic recipe is 1 part peat moss to 1 part soil from your garden or the cheap 40 pound bag of top soil from stores. The key is 50% organic matter (peat moss) for water retention. You can substitute coco coir for peat moss if you wish or make a blend. The video shows you how to add lime and fertilizer to the mix. The 'Premium Recipe' is the addition of bagged manure, compost or hopefully your own compost. It would be 1 part peat moss, 1 part soil, 1 part compost. This builds a great base for container mixes that work well as mixed or you can tweak it for your needs and desires. Adding more stuff is always fun.