The reason mixes ought to be tossed out is primarily due to the ingredients breaking down into smaller and smaller pieces. Once the particles are too small the mix will hold perched water that never drains. A fine particled mix holds lots of water and little air which is unhealthy for plants.

If you will be reusing a mix and wish to 'freshen it up' you are going to want to use coarse particles, not fine particles such as manure which just make the problem worse. There is a limit to how far a mix can be freshened up regardless of what is used. Small particles can/will fill in the air spaces between larger particles.

If you have the ability to remove the bottoms from the containers such that the mix is in contact with the earth then you have a raised bed and the size of the particles becomes less important as excess water will drain into the soil below.

Ultimately what you do is up to you, I just thought I would explain the concept behind what you wish to do and let you do your thing.

I also reuse potting soil and for pretty much the same reasons :-) At least for seasonal container plantings. When I change out the containers, I empty them entirely, remove any visible plant parts, including all roots, add 1/2 to 2/3 fresh 'soil' to the mix and whatever nutrient sources necessary and then refill and replant. The fresh 'soil' is exactly the same as I used previously, generally a formulation very similar to Al's 5-1-1 mix. In the course of a couple of seasons, the entire mix has been replaced at least once. I find this works perfectly satisfactorily for me. Repotting long term container plantings is a whole 'nuther issue and that soil is generally replaced entirely.

I would not include any compost or manure in the mix. It just breaks down too rapidly to be practical. Nor would I use shredded paper or any other ingredient that was inclined to decompose rapidly. And other than succulents, I've never seen the need to topdress or mulch container plantings.

Of course, if there has been any indication of disease problems (and I haven't encountered many), then I would NOT reuse the soil in any new plantings but add it to the garden compost.

I don't do this....

But I do know someone that does. In fact, it's funny, he also uses newspaper, old leaves, chicken poo, and the other things you talked about..

The only way he can get away with it is to repot every month or two and it works, or he'll loose everything if he doesn't.... He is from the Azores.. He would't even consider using anything else, I guess he knows what he's doing. lol. He just does this for his seasonals like gardengal does..:-)

meyermike could you read your above post and re-write so normal people can understand what does he grow ? re=pot every month or two ? "or he will lose everthing" what does this mean? what does it meant he is from Azores ?

People who live in glass houses .....

None are perfect, including you. I found your post confusing, poorly written, and more. I reply to almost everything that interests me, but I chose not to reply to your OP because you were curt and too decided about your course for the level of knowledge and experience you have.

If you try asking polite questions instead of throwing your weight around, you'll get the help you need.

Al

I asked questions and recieved some good answers from justaguy2 and gardengal48, meyermike is trying to say something too, I just couldn't get what he meant to say ,I asked meyermike to read it over ,I hope he replies

I don't reuse pot mixes for a number of reasons. They contain too much organic material that is too fine and thus they trap water and turn to sludge in the bottom of your pot. They may contain disease organisms, fungi, bacteria, parasites that can attack your plants. If you want to do it properly you could try washing out all the fines through a 1/8" screen, then drying the remains and sterilizing it in a oven for 24 hrs. In my view it isn't worth it.

I reuse container soil all the time. I make my own mix from Al Tapla's 511. I only do this for one year, and then start again from scratch.

I rotate the types of vegetables that would grow in a container. Example, if I was growing cucumbers in a container when I replant I might grow cabbage. Something that does not share common diseases.

It has been fine for me, I have to ad sulfer to the mix as my well water is alkaline and after a couple of months PH is about 8 and you can see the difference. My okra love the sulfer.

I do it because I cannot stand waste. Why throw away perfectly good soil. I do not have problems at all. I have cucumber in second season potting soil and it is doing fantastic.

Not sure if you can do this with commercial mixes. The 511 mix is a bit more durable. My two cents. After a year, I rake all the container soil into my grass. The grass is happy, less money spent on fertilizer for the grass, savings... :) $$$

I used to rotate my used container mediums straight into the gardens or onto my compost piles... but I never reused them for other containers.

Since switching to Al's Mix for my potted plants, however, I don't have to re-pot as often. When I do, I'll pitch the old medium into my large raised beds and mix it in.

I have four large beds that I rotate yearly, using three for vegetables and letting one sit fallow to collect all the used soil and readied compost. By the following spring, the fallow one is filled up and ready to plant.

The difficulty in answering this question always arises from not knowing what your original soil, that you now wish to reuse, was comprised of. In the case of one of Al's mixes where you know exactly the original composition, it is possible to replace the organic ingredient that has been consumed and make a reasonable good mix for at least another season. A small adjustment for PH may also be needed depending on your new use. Of course it is a monetary consideration. Al

I am re-using my soil this season, and making new.

Last years was much more course than most would choose. It was also more fresh bark. now it is slightly composted, smaller. it looks a lot not like the particle sizes that most people would have started with the first time. I'm using the old stuff mostly for potted plants, and the new stuff for the veggies in the greenhouse. I only used soil that I think was clean - that is, no obvious signs of disease on the plant last year. I know that's not a sure thing, but that's a risk. I'll stop re-using the first time I have troubles though!

As for waste? no one suggested throwing it in the trash, it's just not always good for container plants. It could be an incredible amendment to an in ground garden, bad spots on the lawn, etc... don't just throw it away, there is always another use. Maybe not container gardening.

I'll probably get in trouble for stating this, but I reuse my container mix every year. I only grow annuals and they do well. My containers are deep and I know the roots only go down about a foot. I remove the top 1/3 and add a little fresh bagged soil and mix some small bark or perlite. Sometimes I just stick the flowers in the old soil.

I fertilize and the plants grow and look nice. I pack them in. In my mind the soil is an anchor and substance to hold water. My containers grow on a hot deck with full sun exposure. I wouldn't do this with plants I wanted to carry over year to year but it has worked well for the 30 years I've been doing it.

Jane

I only get to grow for 4 1/2 months at maximum , many of you use your soil for twice that long in a season. I feel if I have to replace the soil every year it isn't worth it.I do intend to keep a watch for how the soil drains,and when needed be replaced,( as drainage is #1 priority)but I am confident I can get a few years more use from just ammending it. I am a tomato and peppers guy, not going for a record harvest or a prize winner.I did 2 containers with a crappy soil that will not be reused as it drained poorly

How big are your containers with all this left over soil?

Everytime I plant the same, I get huge plants that fill the entire container with their roots and no soil leftover to spare! "One" pepper plant filled a five gallon bucket!

It must be the porous soil I use that Al has taught me to make...The roots love it.

My neighbor is from the Azores....The islands off of Portugal...He's an ole timer who believes in growing entirely like you do, an expert from what he says.
The thing is, he has to constantly watch for root rot and diseases, not to say an entirely nutritional deficient mix, and, has to constantly repot every month or two or his plants will stay stunted and keep yellowing..By the way, he will use Fish Emulsions too along with MG that he says helps.
When he comes over to my yard to compare quite often, mine look alot more robust..We laugh about it, but he still refuses to try a new way..
I respect that though..He still loves his hobby, his own way..I admire his hard work..

Lol, he spends even less money than you, he just digs up the dirt from his backyard, throws the ingrediants together, and presto!!..:-)

I suppose a "short" growing season might allow you to grow like this too...

Hope you understand this time..:-)

Mike