Maintaining Soil Life in Containers - is it practical, or do we need to feed container plants?

[Meadowlark]

Take fertilizers out of the equation and suddenly you find that your container environment is lacking.

No, not here. The fertility is in place when the growing starts.... from carefully maintained garden soil or from cover crops incorporated into the container soil prior to growing the crop. Works perfectly. No teas, no nothing but water.

 

[Susan BBPM]

No, not here. The fertility is in place when the growing starts.... from carefully maintained garden soil or from cover crops incorporated into the container soil prior to growing the crop. Works perfectly. No teas, no nothing but water.

Yes, so you said in the thread that you've started, comment on which is strictly limmited (by you) to YOUR experiences.

My experiences differ from yours and that's what I started this thread to explore. Remember? xx

 

[Meadowlark]

I don't like using containers because I have to water them too much. However, I do have a couple large containers and I treat them just like I do with my soil in the yard.

I filled them halfway with sticks/logs, branch cuttings and leaves (so I didn't have to dig up so much soil) and then put normal soil from my yard into the container.

I always practice chop and drop and occasional heavy mulching to keep level of soil up and I always have something growing in there, including "weeds".

This keeps the soil much better than any purchased garden "soil".

Another voice of reason!!

Purchased garden soil is an anathema to me. Not using prime garden soil in your containers is really out there.

Only thing I do different than you is use "green manure". I have a study going to determine the effectivity of green manure. I believe it is huge..but soil tests will provide actual scientific data.

 

[skinyea]

What size containers?

It just doesn't work well for me (except in very large containers). Things will grow, but they grow MUCH better when I fertilize with comfrey tea or compost tea. (OR if i put them in the ground).

So for example, I've got hubbard, butternut and acorn squash growing in various places in the garden. (In the ground, in a container with fresh compost and regular feed, and in a container that I'm treating the same way as garden beds). The winner is by far the squash in the container with fresh potting compost and feed. Second is in the ground. The container being treated like beds is trailing behind.

It works fine in a huge container (polytunnel raised bed 13 x 3 x 2 foot), but the smaller the container the quicker things go pearshaped.

CPP puts it down to poor drainage in a container, but I've never experienced drainage problems. For me it's drying out too quickly that's the problem.

We have unpredictable weather. Sometimes we have lots of rain and sometimes we have none for days (or weeks on occasion). So for example, you could automate watering but it would need to be something pretty sophisticated to work out when it last rained and whether any watering was needed. Sometimes you don't need to water a container for weeks on end because it rains so often, but then one day you suddenly notice it's dried out and the plant is wilting. The plant will recover with watering but I suspect a lot of damage is done to the soil life in the container. If you're regularly watering with comfry, compost or worm tea that keeps soil life boosted.

I mean, bottom line is that it doesn't work in my climate. My best guess is because it's too easy for the soil life to be killed off in a smaller container (probably due to drying out rather than waterlogging).

There are other factors I'm considering.

In garden beds you have the advantage of roots of other plants, mycorrhizal network etc.
You don't have this in containers, but if you're feeding with organic fertilizerson a regular basis it makes up for this weakness.
Take fertilizers out of the equation and suddenly you find that your container environment is lacking.

I use 5 gallon or 10 gallon tubs. Most are set up for HK so watering is an issue. But Tomatoes, Peppers, Beans, okra Potatoes. no issues. I did try Butter nut squash last year. I did get more production from the garden, but the Container squash grew 7 squash so I would call that a success.

 

[Meadowlark]

Yes, so you said in the thread that you've started, comment on which is strictly limmited (by you) to YOUR experiences.

My experiences differ from yours and that's what I started this thread to explore. Remember? xx

That sounds a lot like your "ideal" claim. What I said was I wanted "hands on personal" experience from any grower here not propaganda from the internet.

 

[Susan BBPM]

I use 5 gallon or 10 gallon tubs. Most are set up for HK so watering is an issue. But Tomatoes, Peppers, Beans, okra Potatoes. no issues. I did try Butter nut squash last year. I did get more production from the garden, but the Container squash grew 7 squash so I would call that a success.

I can't say I've tried every crop as it's mainly squash that I like to grow in my containers on the patio. So your experience matches mine.

They grow, but not as well as in garden beds. Why would that be - do you have any thoughts on why your beds do better?

I have found that the same containers, filled with fresh compost, manure and other bits of bobs, and fed regularly with fertilizer - BEAT my garden beds.

So in other words - in the beds I can feed the soil and the soil life then feeds my plants succesfully. Added fertilizer makes no difference. But in a container, feeding the soil works to a degree but not as well as in a bed. I've never tried going beyond two years without changing out the soil as by year two it's already going downhill.

In a container I have found that feeding the plants (or at least, supplementing feeding the soil with fertilizer) produces the absolute best results.

In my HUGE polytunnel container (deep raised bed) it works exactly like my garden beds. Although - I've only ever grown peppers, tomatoes, potatoes in there so in light of what you said it might be that they're less fussy.

 

[Susan BBPM]

I'm just considering one possibility here - mycorrhizal network.

"The word mycorrhizal relates to "myco" (fungi) and "rhiza" (root). It refers to the symbiotic relationships that fungi have with plant roots, aiding absorption of nutrients and helping them grow. Mycorrhizal fungi pass water and nutrients to the plant, and the plant in turn supplies the fungi with some of the food that it generates by photosynthesis – the process by which plants use sunlight to transform water and carbon dioxide into oxygen and energy.

Because the fungi are far more extensive than the plants’ roots alone, they efficiently ‘mine’ the soil for nutrients and water, and the food from the plant boosts the fungi growth."

Complete Guide to Mycorrhizal Fungi | BBC Gardeners World Magazine

What is mycorrhizal fungi and how does it work? Find out in our complete guide, from BBC Gardeners' World Magazine.

www.gardenersworld.com

According to the Gardeners World article that I've quoted the above from, 90% of plants make use of mycorrizal network. (Brassicas don't).

Containers don't have access to this network, so assuming it's working for you in your beds (and if you dig your beds it may not be) then you'll be at a disadvantage when you use containers - they won't have access to it.

However, if you make up for that deficit by feeding the plants with organic fertilizers you make up for it.

It's one possible explanation. But I've tried bottomless containers and it really doesn't help much.

 

[skinyea]

I can't say I've tried every crop as it's mainly squash that I like to grow in my containers on the patio. So your experience matches mine.

They grow, but not as well as in garden beds. Why would that be - do you have any thoughts on why your beds do better?

I have found that the same containers, filled with fresh compost, manure and other bits of bobs, and fed regularly with fertilizer - BEAT my garden beds.

So in other words - in the beds I can feed the soil and the soil life then feeds my plants succesfully. Added fertilizer makes no difference. But in a container, feeding the soil works to a degree but not as well as in a bed. I've never tried going beyond two years without changing out the soil as by year two it's already going downhill.

In a container I have found that feeding the plants (or at least, supplementing feeding the soil with fertilizer) produces the absolute best results.

In my HUGE polytunnel container (deep raised bed) it works exactly like my garden beds. Although - I've only ever grown peppers, tomatoes, potatoes in there so in light of what you said it might be that they're less fussy.

I would say it was more my fault. I tend to get the same production from container to garden. The Butternut grew a ton of leaves just didnt fruit well. It was late in the season and more of an experiment than anything else. I had 1 extra butternut plant and put it in the container.

 

[Susan BBPM]

I would say it was more my fault. I tend to get the same production from container to garden. The Butternut grew a ton of leaves just didnt fruit well. It was late in the season and more of an experiment than anything else. I had 1 extra butternut plant and put it in the container.

intereting! So absolutely no benefit to growing in garden beds in your part of the world then?

 

[skinyea]

intereting! So absolutely no benefit to growing in garden beds in your part of the world then?

it is easier admittedly due to how much you have to water the containers, but as far as production goes, if watered correctly same.

Crimson clover,a clover mix, legumes etc all work in the containers over winter just as good as they do in garden.

 

[Susan BBPM]

it is easier admittedly due to how much you have to water the containers, but as far as production goes, if watered correctly same.

Crimson clover,a clover mix, legumes etc all work in the containers over winter just as good as they do in garden.

And that I think is key - if watered correctly.

If a container dries out completely the plant wilts, you water it and it recovers. No real harm done. But soil life will die or flee your container.

A bed is far more forgiving. I move my worm farm to my polytunnel bed in the winter - if it gets too cold I get a mass exodus into the bed.

If you live in a very predictable climate (no rain all summer) then you can set up irrigation to make sure you've got just the right amount of water going into your containers. But in climates like mine you can have days on end of torrential rain, then drought, then rain one minute and scorching sun and drying winds the next. The only way to keep containers correctly watered is to be checking them constantly. Mistakes happen over the year and each time the soil life is killed off.

Also, how do you water them? We have water butts but in drought conditions they don't go far. So you need to use a hose and mains water which is full of chlorine. Again, not ideal for the soil life.

I think that's a big part of it - you'll never get the same level of soil life in a container as you get in garden beds. The bigger the container the better it will get, but I think it'd need to be VERY big to match a garden bed. For example, I tend to find some worms in my containers but nowhere near as many as in the garden beds. And when weather conditions aren't right they take flight to the garden beds.

But I suspect there's a lot more going on in our garden beds. Such as mycorrhizal network.

But you can grow veg hydroponically - so even without soil you can grow great veg with the right fertilizer. More work though.

i think I'm going to end up ditching containers and building raised beds on my patio.

 

[skinyea]

A far as watering goes, this is a rough year so far. Rain just keeps missing me. Rains all around but not here. I had to water my garden i think 3 times all year. it literally rained the next day 1 time unexpectedly. This year I have watered 4 times already.
I have rain buckets set up that can usually just use. But no rain equals no rain in the rain buckets. so I have hoses set up to water.

The Containers, again I can usually save enough rain water to use, but not this year. hose again.

I think Meadowlark s right, the more organic matter you can use, and the more you figure out what cover crops work best in your climate, the better every garden is. in the ground or in pots.

 

[Susan BBPM]

A far as watering goes, this is a rough year so far. Rain just keeps missing me. Rains all around but not here. I had to water my garden i think 3 times all year. it literally rained the next day 1 time unexpectedly. This year I have watered 4 times already.
I have rain buckets set up that can usually just use. But no rain equals no rain in the rain buckets. so I have hoses set up to water.

The Containers, again I can usually save enough rain water to use, but not this year. hose again.

I think Meadowlark s right, the more organic matter you can use, and the more you figure out what cover crops work best in your climate, the better every garden is. in the ground or in pots.

Yet you're getting steller results adding very little organic matter. How much organic matter do you get from 1 or 2 square foot of clover each year? A couple of teaspoons tops once it breaks down? Absolutely nothing else going in, and hungry crops like squash and potatoes coming out? I'm not doubting you BTW. But just pointing out that you're adding next to no organic matter over the years is all you do is grow a bit of clover once a year.

I follow Charles Dowding's no dig approach. The basic principle is that you feed the soil life and not the plants. Dowding is a pioneer of organic gardening and he helped develop the no-dig approach. He's been growing commercially (and intensively) using these methods for many years. He's distilled it down to adding just 1 inch of garden compost to the top of his beds every December. No digging in. With nothing else added to his beds he is able to grow crop after crop without any amendments in between. He doesn't recommend cover crops - primarily becaue they aren't necessary and he doesn't see the point in using them when he could be using his beds for a cash or food crop. He has also pointed out that in our climate and in clay soil green manures can stagnate under the soil rather than decompose. And of course a major problem here is that they create a slug and snail habitat.

In a garden bed, that one application of compost in December will support 2,3 - even 4 crops. He doesn't leave beds empty until the end of the growing season. He starts everything out in plug trays so that when one crop is harvested then next has already got a one month head start. So INTENSIVE growing with no added nutrients or organic matter (except that 1 inch in December).

It works brilliantly for me in beds, but as I say - in containers I find that I get much better resuts with fertilizer. I could (and have) grown a crop of potatoes followed by carrots in a container without adding anything. But the yeild won't be as good as in my beds. Nor will it be as good as a container I've fertilized.

I do actually use cover crops over winter, but primarily to grow material for composting. Sometimes it's killed by the frost so breaks down in situ but I can't say I've noticed benefits over and above what I get from that one inch of compost.

I guess it's possible that no dig leads to better resuts in garden beds than your approach. It might not be that my containers are struggling more than yours, but rather that my beds are doing better. No dig might be unleashing the benefit from the Mycorrhizal network for example - something that tilling destroys. If I'm getting a big boost from that then that would explain why containers (without fertilizer) are so lackluster.

Regardless - I think I'm going to end up building raised beds on my patio. Beds aren't only better in my climate - they're much, much, much less work!!

 

[skinyea]

I would say it is more than a couple of teaspoon drops, Crimson clover, regular cover, leaves etc. peas from other containers, so far it has been enough.

 

[Susan BBPM]

I would say it is more than a couple of teaspoon drops, Crimson clover, regular cover, leaves etc. peas from other containers, so far it has been enough.

So contrary to what you said intitially you're not relying on the green manure you grow in your container. You're bringing in leaves and peas from elsewhere.

I'm bringing in whole lawns full of clover, peas, beans, grass, comfry, nettles, weeds, leaves, kitchen scraps, cow and horse manure etc - in the form of garden compost. Roots of anything grown (in some beds up to 4 crops in a year) is left to rot down. But it's not enough in a container *in my environment*. It works brilliantly in beds and even very large containers.....but not in patio containers. Likely for a combination of the reasons already explained.

i can get 2 - perhaps 3 years out of a patio container for flowers and less hungry crops (although fresh potting soil and fertilzier gets bettter results), but for squash I get best results replenishing each year with plenty of compost and manure and in addition feeding with compost teas etc throughout the growing season.

In my polytunnel raised bed (12 ft x 3ft x 2f high) I'm now on year 4 growing potatoes, then tomatoes, cucumbers and peppers then covering with an inch of compost for the winter. Potatoes go in Feb, Tomatoes (already fairly large in pots) go in May when the potatoes come out. Tomatoes come out about November and then a layer of compost goes down until the following Feb. I tend to add another thin layer of compost from the hotbin in feb - simply because I put the hotbin in the polytunnel for winter and it's easy to just dump it on the beds when I move it back out in spring. Worm farm also goes in and that leaches some nutrients over winter. There isn't enough light to grow through the winter here so best you can do is keep something dormant in the ground until spring - which isn't going to take nutrients out of the soil. I've done that once, but I only have the bed empty for 3 months so I find it's more bother than it's worth. The layer of compost protects the soil. The big polytunnel bed was initially filled with garden soil, logs, twigs, leaves, manure, compot etc.