Re-using container soil - Diseases?

tam91 · February 17, 2011

In the past, I've dumped out the soil in my containers and sterilzed them each year. But as I'm wanting to increase the number of varieties, that's starting to be a lot of soil!

So I am wondering - which diseases can overwinter in the soil? I did pull out the plants and dispose of them.

I think I had some Septoria, could have been a little blight, and the strange un-named crud that affects black tomatoes. I was able to control everything with fungicides, and all the plants survived.

But - if I were to re-use my soil, are any of those diseases likely to be in there?

ContainerTed · February 17, 2011

Tam, I always reused my container mix. At the end of the growing season, I would empty all the buckets into a large pile on top of a large heavy duty tarp. I would add some mulched-up leaves from safe trees and any other mulched up greenery I had available. Then I would throw in a light dusting of dolomite lime and some generic 10-10-10 slow release fertilizer. The lime and the ferts would dissolve over the winter. Then I would mix it all up very well.

Making sure the moisture level was good (like a compost pile) I would wrap it all up and place some bricks and concrete blocks on top to keep the rain out, I would let it compost all winter. At least once a month, I would uncover it and roll it over. You could tell the composting heat was working by touching the tarp. The heat was warming the whole thing.

That went on for at least three years down in North Georgia. My tomatoes and peppers loved it.

In the spring, I would open the tarp and let it air out for a few days. Then to load my buckets, I would use this mix:
5 shovels of old mix
1 shovel of composted manure or mushroom compost
2 shovels of new mix
1 hand full of dolomite lime
1 hand full of 10-10-10 fertilizer
1 hand full of Tomato-Tone

Containers suffer from "wash-out" of the nutrients with the increased watering required. Hitting the mix with nutrients before the composting seemed to bring life back into the mix. Adding more at pot-up would allow more dissolving during the growth time.

Hope some of this helps your confidence. Composting is one of the ways to kill off pathogens (if the temp gets high enough). One of our experts will have to talk to Septoria, but I had a plant from "Bonnie Plants" that had it and, yet, I didn't have it the next season, although I reused the mix.

Ted

RayR · February 17, 2011

Septoria, like Early Blight is not a soil born fungus, the spores travel through the air and overwinter in debris from any plant in the nightshade family which includes tomatoes, eggplant, peppers, potato, and some weeds. Changing soil won't help there. Best defense besides fungicides is always pruning infected leaves and stems and destroying all debris from those plants at the end of the season. Mulching with compost can help also since the good organisms in the compost can kill off or crowd out the bad spores that land on the ground and would otherwise splash up when it rains.
Septoria is always a problem here, it's a tough one to eliminate completely since it can blow in from beyond your property.

tam91 · February 17, 2011

Composting would be interesting, but that'd have to be next year if I can (obviously I didn't do it this year).

None of the major tomato diseases overwinter in the soil?

fortyonenorth · February 17, 2011

I believe bacterial wilt and Fusarium wilt are soil-borne - maybe Verticillium, too??

I've never understood the "throw away your container soil" approach. I grow in big containers (about 90 gal for 2 plants), so I don't remove or replace my soil. At the end of the year, I remove any mulch to the compost heap. Then, I take a soil sample and apply ferts according to a soil test. Last year this meant adding a considerable amount of P and K as well as trace minerals such as copper, iron and boron. Then I planted a cover crop of rye/vetch. I'll turn this under here in a few weeks for a few containers and plant radishes and peas. In the other containers, the cover crop will grow until the first of May - about two weeks before the tomatoes go in. I'll add a few shovelfuls of compost at this time. After the plants go in I mulch heavily with straw or pine bark fines.

tam91 · February 17, 2011

OK, well I haven't had any wilt I don't believe.

I don't actually throw it away - it just goes into the garden where beans, peas, etc - other crops, grow.

Where do you get a soil test done?

fortyonenorth · February 17, 2011

I use Logan Labs in Ohio (http://www.loganlabs.com/) They follow the ideas of mineral balancing which I like. You can also check with your nearest cooperative extension service.

I can't remember where you are, Tam...

DuPage County is here: http://web.extension.illinois.edu/du...TOKEN=35973222

Kane County is here: http://web.extension.illinois.edu/ka...TOKEN=35973222

tam91 · February 17, 2011

Thank you. I'm in McHenry county - but I presume they probably do it to.

ovenbird · February 17, 2011

I've read that tomatoes actually like to grow in the same soil. A lot of tomato diseases get into the soil from diseased plant parts, so keep a mulch barrier on top of the soil and keep plant droppings cleaned up.

rsg2001 · February 19, 2011

I've had problems now and then with keeping the soil in self-watering containers year over year. I've never quite figured out which diseases were the big issues. So I dump the mix from the smaller containers (I reuse it in the back area of the yard where I grew flowers last year), and go fresh. But in the giant self-watering pot (which is 3 feet by 3 feet) I replace about 1/3 of the mix. I always put fresh nutrients in - last year started using Ocean Solution which gets good reviews on micronutrients.

biscgolf · February 20, 2011

imo you're best off composting it for a season if you want to re-use your container soil...this is what i do.

dice · February 21, 2011

I let it dry out, then sift it with an aluminum-framed window
screen to shake out silt (from the breakdown of organic matter)
before reusing it. I mix in some fresh peat or compost or leaf
mold to replace the removed silt. One can used bagged
container mix or a custom made mix (3-2-1, etc) for that, too.

Peat lasts for as many as 5 years before it breaks down to silt,
but I have to buy it, and it grows back at 1/25 of an inch a year
in peat bogs, so it is not really "sustainable" gardening, whereas
tree leaves are replaced every year if one can collect enough
of them. Compost is plant food as well as structure in a
container mix, but I rarely have enough of it for all of the plants
in containers and garden beds, so I need to use other things,
too, to replace decayed-to-silt organic matter in container mix.

That does not do anything for soil diseases (we do not get
fusarium up here, and I have not had bacterial wilt, but we
do have verticillium in the native soils around here). I have
had few problems with those in containers. I have used
lime-sulfur to treat a container where the previous year's
plant appeared to be suffering from verticillium (soil drench
at a tablespoon per gallon of lime-sulfur concentrate,
normally used as a spray on trees or roses), but if it is only
a rare container that has the disease, it makes more sense
to simply dump that one out somewhere where the plants
growing there are not susceptible to the disease, disinfect it,
and start fresh.

Farmers have been finding that growing mustard and oilseed
radish cover crops in fall-winter will repress some soil diseases.
(I assume that they simply disc or till the cover crop top growth
into the soil in spring before planting.)

February 17, 2011	#1
tam91 Tomatovillian™ Join Date: Aug 2010 Location: Crystal Lake IL Posts: 2,484	Re-using container soil - Diseases? In the past, I've dumped out the soil in my containers and sterilzed them each year. But as I'm wanting to increase the number of varieties, that's starting to be a lot of soil! So I am wondering - which diseases can overwinter in the soil? I did pull out the plants and dispose of them. I think I had some Septoria, could have been a little blight, and the strange un-named crud that affects black tomatoes. I was able to control everything with fungicides, and all the plants survived. But - if I were to re-use my soil, are any of those diseases likely to be in there?

February 17, 2011	#2
ContainerTed Tomatovillian™ Join Date: Jul 2008 Location: 6a - NE Tennessee Posts: 4,538	Tam, I always reused my container mix. At the end of the growing season, I would empty all the buckets into a large pile on top of a large heavy duty tarp. I would add some mulched-up leaves from safe trees and any other mulched up greenery I had available. Then I would throw in a light dusting of dolomite lime and some generic 10-10-10 slow release fertilizer. The lime and the ferts would dissolve over the winter. Then I would mix it all up very well. Making sure the moisture level was good (like a compost pile) I would wrap it all up and place some bricks and concrete blocks on top to keep the rain out, I would let it compost all winter. At least once a month, I would uncover it and roll it over. You could tell the composting heat was working by touching the tarp. The heat was warming the whole thing. That went on for at least three years down in North Georgia. My tomatoes and peppers loved it. In the spring, I would open the tarp and let it air out for a few days. Then to load my buckets, I would use this mix: 5 shovels of old mix 1 shovel of composted manure or mushroom compost 2 shovels of new mix 1 hand full of dolomite lime 1 hand full of 10-10-10 fertilizer 1 hand full of Tomato-Tone Containers suffer from "wash-out" of the nutrients with the increased watering required. Hitting the mix with nutrients before the composting seemed to bring life back into the mix. Adding more at pot-up would allow more dissolving during the growth time. Hope some of this helps your confidence. Composting is one of the ways to kill off pathogens (if the temp gets high enough). One of our experts will have to talk to Septoria, but I had a plant from "Bonnie Plants" that had it and, yet, I didn't have it the next season, although I reused the mix. Ted __________________ Ted ________________________ Owner & Sole Operator Of The Muddy Bucket Farm and Tomato Ranch

February 21, 2011	#12
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	I let it dry out, then sift it with an aluminum-framed window screen to shake out silt (from the breakdown of organic matter) before reusing it. I mix in some fresh peat or compost or leaf mold to replace the removed silt. One can used bagged container mix or a custom made mix (3-2-1, etc) for that, too. Peat lasts for as many as 5 years before it breaks down to silt, but I have to buy it, and it grows back at 1/25 of an inch a year in peat bogs, so it is not really "sustainable" gardening, whereas tree leaves are replaced every year if one can collect enough of them. Compost is plant food as well as structure in a container mix, but I rarely have enough of it for all of the plants in containers and garden beds, so I need to use other things, too, to replace decayed-to-silt organic matter in container mix. That does not do anything for soil diseases (we do not get fusarium up here, and I have not had bacterial wilt, but we do have verticillium in the native soils around here). I have had few problems with those in containers. I have used lime-sulfur to treat a container where the previous year's plant appeared to be suffering from verticillium (soil drench at a tablespoon per gallon of lime-sulfur concentrate, normally used as a spray on trees or roses), but if it is only a rare container that has the disease, it makes more sense to simply dump that one out somewhere where the plants growing there are not susceptible to the disease, disinfect it, and start fresh. Farmers have been finding that growing mustard and oilseed radish cover crops in fall-winter will repress some soil diseases. (I assume that they simply disc or till the cover crop top growth into the soil in spring before planting.) __________________ -- alias

February 17, 2011	#3
RayR Tomatovillian™ Join Date: Jun 2010 Location: Cheektowaga, NY Posts: 2,466	Septoria, like Early Blight is not a soil born fungus, the spores travel through the air and overwinter in debris from any plant in the nightshade family which includes tomatoes, eggplant, peppers, potato, and some weeds. Changing soil won't help there. Best defense besides fungicides is always pruning infected leaves and stems and destroying all debris from those plants at the end of the season. Mulching with compost can help also since the good organisms in the compost can kill off or crowd out the bad spores that land on the ground and would otherwise splash up when it rains. Septoria is always a problem here, it's a tough one to eliminate completely since it can blow in from beyond your property.

February 17, 2011	#5
fortyonenorth Tomatovillian™ Join Date: Jan 2010 Location: NW Indiana Posts: 1,150	I believe bacterial wilt and Fusarium wilt are soil-borne - maybe Verticillium, too?? I've never understood the "throw away your container soil" approach. I grow in big containers (about 90 gal for 2 plants), so I don't remove or replace my soil. At the end of the year, I remove any mulch to the compost heap. Then, I take a soil sample and apply ferts according to a soil test. Last year this meant adding a considerable amount of P and K as well as trace minerals such as copper, iron and boron. Then I planted a cover crop of rye/vetch. I'll turn this under here in a few weeks for a few containers and plant radishes and peas. In the other containers, the cover crop will grow until the first of May - about two weeks before the tomatoes go in. I'll add a few shovelfuls of compost at this time. After the plants go in I mulch heavily with straw or pine bark fines.

February 17, 2011	#9
ovenbird Tomatovillian™ Join Date: Nov 2007 Location: Eastern Iowa Posts: 27	I've read that tomatoes actually like to grow in the same soil. A lot of tomato diseases get into the soil from diseased plant parts, so keep a mulch barrier on top of the soil and keep plant droppings cleaned up.

February 19, 2011	#10
rsg2001 Tomatovillian™ Join Date: Jun 2006 Location: New York Zone 6 Posts: 479	I've had problems now and then with keeping the soil in self-watering containers year over year. I've never quite figured out which diseases were the big issues. So I dump the mix from the smaller containers (I reuse it in the back area of the yard where I grew flowers last year), and go fresh. But in the giant self-watering pot (which is 3 feet by 3 feet) I replace about 1/3 of the mix. I always put fresh nutrients in - last year started using Ocean Solution which gets good reviews on micronutrients.

February 20, 2011	#11
biscgolf Tomatovillian™ Join Date: Jan 2011 Location: Virginia Posts: 353	imo you're best off composting it for a season if you want to re-use your container soil...this is what i do.