The key to having a great container garden is to use the right soil. Soils for container gardening should be one of the soilless ones such as Promix or Fafard Sunshine Mix.
I mean a peat based soilless soil mix that is based on peat moss. They often contain perlite to increase the drainage or vermiculite to do the same thing on a short term basis.
They often contain a small charge of fertilizer that will get your plants started but only for the first week; after that all feeding is up to you. They will also contain a wetting agent that will allow you to easily wet the mix and have water penetrate. Never Use Real Garden Soil Or Any Product Containing Soil
Real soil from the garden compacts under the pressure of repeated waterings. It literally turns into concrete and then your tender plant roots will not be able to grow. Not grow much- but grow at all. Your plant growth will simply stop and along with it all flowering or fruiting. Never use real garden soil in a container.
So, we use an soilless soil mix and I don’t mean a bagged topsoil, miracle soil, super soil or a bagged potting soil. Those still contain too much soil and/or sand and will compact.
I mean a peat based soilless soil mix that are based on peat moss. This is the way to have a great container garden.
Don’t spend extra money for soilless mixes promising added microorganisms. Research has shown most soils don’t deliver living organisms.
Can You Mix Your Own?
I have experimented with mixing my own mostly using peat moss because I used to have too many large containers and I use a significant amount of soil every year. (My Scottish ancestry means I’m always looking for inexpensive but effective gardening techniques)
I’ve found that if I use peat moss mixed with up to 30% *good* compost, then I get an excellent product and the plants grow quite nicely.
Bagged manure is not good compost but it did work quite nicely when mixed at 10-15% of the mix. As a soil for container gardening, the manure worked but not as good as compost.
But for the most part, I use soilless mix and reuse it from year to year by adding compost (see video below)
BUT let me point out that I’ve gardened using soilless mixes (from different manufacturers) for over 30 years now – in the nursery and home garden – and I’ve grown in a ton of different mixes. This gives me the ability to modify my watering and feeding based on what I’m seeing in my plant’s growth.
Which is another way of saying if you’re a beginner, you may want to stick to the prepared mixes and reuse them as per the video below.
Can You Reuse Container Soil?
Absolutely and here’s how I do it
Should You Mix Your Own?
Not the difference between “can” in the previous paragraph and “should” in this paragraph.
Allow me to be frank. If you’re anything but a very good gardener, this isn’t the first step you should make.
My .02 is you should start with a commercial soilless mix and experiment yourself to see if you can replicate my success.
One problem is you may find it works one year and then not the next – there’s no consistency there.
Bottom Line:
Use a soilless mix and mix good compost into it every year to recharge the soil. Then feed and grow your plants as normal