How can I compost diseased garden waste (e.g. blighted tomato plants?)

Hey All - I couldn't find a previous thread on this, but I feel like it has to have been discussed in depth so feel free to link a thread if you know of one.

I had an awesome overall year for tomatoes, at least for me! About 250 lbs. from 6 Romas, 6 Matt's Wild cherries, and 12 other assorted indeterminate varieties, some of which didn't even perform very well. I finally pulled them all and cleaned up yesterday.

My 10 cubic-foot pull-behind cart is full and mounded about as high as it can go between the plant material and straw I mulched with. My plants were nice and healthy longer than I've ever managed before, but eventually all had pretty bad disease - I think either late blight or septoria leaf spot or both. I just can't bring myself to throw away this much organic matter! SURELY there's a safe way to keep it in my ecosystem (sorry idk the right word to use but I think you'll get my meaning) without inoculating my compost pile with disease spores.

Does anyone have a good way to accomplish this? I was thinking maybe get a metal drum and basically sterilize it all by cooking it over a fire? Or even putting a lid on that drum and making biochar out of it maybe?

I have a ton of book learning around this stuff but am just getting to where I'd call myself an "experienced" microfarmer and have a ton to learn practically speaking. Thanks so much for any info!

I think the best way and the most effective way is to burn garden waste to ensure that all of the infected plant tissue and spores as examples are killed, and then return the ash to your garden soil or sprinkle the ash into a compost pile so the minerals are recycled. I think the biochar method you mentioned will work also as it will be hot enough to kill everything. I am unsure how much charcoal will result from soft tissued plants such as tomatoes but it's certainly worth a try.

You might want to investigate hot composting. You would have to do it right and make sure the internal temperature is hot enough to kill all pathogens. In theory with the right ingredients and following the steps, you could have a healthy and useable soil in three weeks.

Here are a few threads on hot composting and / or blight discussed here on permies:

https://permies.com/t/154001/day-Berkeley-hot-composting

https://permies.com/t/137275/Hot-Composting-Potato-Soil

https://permies.com/t/164822/rid-soil-tomato-blight

Just compost it as normal blight isn't transmitted via compost it requires living tissue to survive. If you still have host plants around that could carry the disease over winter dig a trench and bury everything that will stop any spores finding a new host.

Imagine billions of ~10 micron spores looking for equally tiny nooks and crannies to settle in for long term lodging and eventual colonization. These are tough little armored life-packages that can wait years for the proper conditions to bloom again. They move around your property via the wind, infected garden carts, contaminated pruners, trouser legs, boots and so on. At first, they were fairly contained in your garden. Now they are moving around your property in a wider and wider range, clinging to you, your garden tools, your dog and other garden visitors. Setting the diseased material on fire creates smoke plumes that the tiny particles can ride and travel even greater distances. Start by assuming that your garden is a tomato disease vector, the disease is traveling far and wide, and you’ve got to manage this plague. If you have to compost the material in your yard, carefully bury the diseased bodies in your existing tomato garden, put a marker up that says, NO NIGHTSHADES HERE UNTIL 2027. Six years of alternate or cover crops could naturally clean up this area. Wash your tools in water and allow the water to go into your contaminated zone. Now disinfect your pruners, your rakes, your cart and all other gear using ethanol and a hand held blow torch for metal surfaces. Given the spread of disease beyond the tomato garden, I’d either skip tomatoes entirely next year, or plant disease resistant varieties as far from this year’s as possible. Don’t infect your compost: the heat will not kill spores. Take this problem seriously so you will have awesome tomatoes in the future.

Amy Gardener wrote:Start by assuming that your garden is a tomato disease vector, the disease is traveling far and wide, and you’ve got to manage this plague. If you have to compost the material in your yard, carefully bury the diseased bodies in your existing tomato garden, put a marker up that says, NO NIGHTSHADES HERE UNTIL 2027. Six years of alternate or cover crops could naturally clean up this area. Wash your tools in water and allow the water to go into your contaminated zone. Now disinfect your pruners, your rakes, your cart and all other gear using ethanol and a hand held blow torch for metal surfaces. Given the spread of disease beyond the tomato garden, I’d either skip tomatoes entirely next year, or plant disease resistant varieties as far from this year’s as possible. Don’t infect your compost: the heat will not kill spores. Take this problem seriously so you will have awesome tomatoes in the future.

I envy your dedication to the war against blight! In my garden, eradication doesn't seem feasible. It's omnipresent in the environment; it's been on my tomatoes from year one, and no amount of removal/sterilization seems to affect its manifestation overmuch. Over time, I've come to accept that blight is going to overwhelm my tomatoes towards the end of the season. I've shifted my priority to getting a great harvest before that happens. I grow a wide variety of tomatoes and save seeds from the ones that perform best, and after a couple generations, I get a good crop every year before the blight wins.

I used to throw away all of my blighty tomatoes at the end of the season (and solarize the soil, etc), but nowadays I just compost them. The severity of the blight does vary from year to year, but I don't feel like it's strongly correlated with anything I do in particular. In a bad blight year, everyone in my area has problems. In a good year, everyone reports less blight.

I love the idea of wiping blight out entirely, though. It makes sense that recently-introduced blight could be contained and destroyed, or at least minimized...definitely worth doing if you can swing it!

We have one of those 'junky' gardens that accumulates diverse weeds as well as volunteer plants like tomatillos, some of the hardier heirloom tomatoes and other members of the Solanacae.  We feel we have been rather lucky with both our potatoes and tomatoes when it comes to late blight considering we are in the heart of a major potato production region and one that is known to have late blight problems at times.  For tomatoes, we grow only a few diehards that have produced well over several decades from the seed we keep each fall.  Only Septoria is a perennial problem, but arrives too late in the crop to be of major concern.

My sister in western Wisconsin just experienced what the OP described and lost a LOT of an otherwise great looking crop this year....although not confirmed to be late blight, the symptoms sure matched up well.  The question came up about how to get rid of the vines and infected fruit and given the layout of her garden I would probably recommend burning if possible and composting as a complement or alternative.  Although Skandi R. was largely correct about the need for late blight (assuming it is indeed late blight that is the culprit) to have living tissue for survival, there are disturbing new reports about the *possibility* of late blight strains in the US being able to overwinter on seeds of from plants that had been infected (see below).  Of course in states that have a sizable potato production, if the seed potatoes are infected with late blight, then that year's crop likely will be a Typhoid Mary of the region as the growing plants could well be coming down with the disease and producing more wind-born spores that can spread to neighboring fields.   As this forum is somewhat assuming that you don't want to use more conventional chemical control, then "Living with" the disease may just have to be an option until natural resistance is found, either in your own saved seeds or from other sources, and trying to avoid past plots with which you've had severe problems.  Wish I had something more positive to suggest.

I feed them to the chickens or rather put them in the chicken run. The chickens eat some immediately, but a lot just sits around to be composted by them. That is the hottest compost that I'm going to have. I don't have time for turning piles or measuring browns vs. greens.

I also don't try to eradicate blight, it's just not going to happen. I get a good crop and don't worry about the rest of it.

Mike Bruner wrote:Or even putting a lid on that drum and making biochar out of it maybe?

This was my first thought. KILL IT WITH FIRE🤩🧐🥵😵👿👹

And clean the area as best you can. Topical peroxide sprays. Dilute for soil and/or foliar spray.

I also don't try to eliminate blight(s) or even identify them. Too much of it and my garden is too small. I cleaned my tomato trellises just a few days ago. All I do is cut the vines off and drop them right there where they grew and pitch some pulled weeds and a little compost or soil on top. Next year, beans or something will get that spot, tomatoes will go where beans or something were this year.

All I've done for a long time, if I have the choice, is to save my seeds from plants that show less damage from disease. This applies to all crops and seems to work pretty good.

I would chop up all that material and use it in the next batch of hot compost. With temperatures reaching over 65°C for two days and two successive turns, (6 days in total at 65°C or more) all the material should have been cooked thoroughly enough to kill the pathogens and any seeds that may have been lurking in the feed material.   Once cooled the compost can be spread out again or left to mature for a few months.  

Hi Mike,

I feel your pain! No matter how much stuff I throw in my compost pile it always rots down to practically nothing! You start out with a pile that is 4 feet high and wide and 10 feet long and once it's finished you can fit it in a wheelbarrow!  That's just not fair! I never have enough compost. And it hurts my heart when something gets infected with a disease or bacterial wilt or even overrun with millions of aphids. I need all that good organic matter to make more compost. And as a 'permie' I feel like EVERYTHING should get reused, recycled or repurposed! Nothing should be tossed in the trash unless absolutely necessary.

As an avid organic gardener I've spent years reading up on how to kill stuff! Yes, I said kill stuff. Lots of this nasty stuff can be killed if it gets too hot or too cold, too wet or too dry, true enough. But the most common denominator I have noticed is that most of these things need living matter and a tiny bit of moisture to survive. Whether it's dirt or plant material or whatever. So that's the issue I focused on.

So here's what I do when I'm in your situation. Years ago I bought a small box of super heavy duty black lawn trash bags. The really thick ones that will hold up in the sun for a couple of years before they disintegrate. (I still reuse them) I place the infected plants in the bags and and close it up tight so air doesn't get in or out.  I toss them in a corner of my yard and forget about them. By next summer when the temps here reach 100+ I go get the bags which are super hot sitting in the sun. Everything in the bags is dead, dead, and more dead. Hot and dead! But I'm pretty sure the minerals and carbon and good stuff  will still be there. I then dig the remaining dust, crunchy stuff in just one bed and plant my crop. I keep notes each year to remind myself to check and look for any adverse reactions in that spot that I hadn't anticipated. So far it seems to work well. It seems to kill the bad stuff and everything gets reused.  I still wish it was great compost.... but it's the best I can do. Turns out, I like to grow stuff and I like to kill stuff too!!
Happy gardening everyone.

I think this discussion could benefit from stepping back and looking at this from an ecological succession and evolution perspective.

What would be the best way to breed tomato pests/diseases? Grow only tomatoes! Even more effective would be growing only one varietal, or highly inbred cultivars bred in near sterile conditions.

What would be the best way to breed predators of tomato pests/diseases? Compost them non-thermophylically (cool and slow), so as to breed the organisms that eat the problem organisms. This is similar to producing an antibiotic by culturing fungus (ie penicillin) on an auger of a given pathogen.

In addition, we can breed landrace tomatoes that will be bred to handle our local weather and pathogens. Mollison (in Permaculture I or II I believe) recommended allowing an ideal fruit to get beyond ripe, then burying that overripe tomato where you want to grow them next year under mulch, and mark the spot. Select for the strongest seedling in the spring, and transplant the others if desired. It will very likely be very similar to the parent, will ripen in your season and will stand up to your pathogens (as its parents had to).

Previous posts were correct in assuming that the pathogen is already everywhere around your garden, but it was also prevalent enough to get in there in the first place. Its not going away. None of the human or plant pathogens that have successfully evolved through 4.5billion years of natural selection are going away entirely, we have to adapt to live with them.  However, based on comments by Mike McGrath of the You Bet Your Garden podcast/npr/pbs show and former editor of Rodale Organic Gardening Magazine, blight is an overused catchall term that would be better reserved for the true "plant plague" that caused the Irish potato famine. Often it is misapplied for other far more manageable diseases (fusarium, verticillium most commonly). By my understanding, blight will apparently wipe out every nightshade in its path very quickly, and was unlikely to be the culprit if you had a good harvest at all.  Regardless McGrath, as well as those he consults with like Lee Reisch and Dr. Howard Gerritt strongly endorse composting diseased material to breed the consumers of pathogens.

Of course I am just some dude on the internet who hasn't seen your garden so I may be wrong!

What an interesting idea.  “What would be the best way to breed tomato pests/diseases? Grow only tomatoes! Even more effective would be growing only one variety, or highly inbred cultivars bred in near sterile conditions.   What would be the best way to breed predators of tomato pests/diseases? Compost them 'non-thermophylically' (cool and slow), so as to breed the organisms that eat the problem organisms. “

I guess that's one way to fix the problem. I think that is probably the very best solution. Just let Mother Nature fix the problem. She's way better at doing these things than we are!

But that made me ask so many questions! Are there currently natural, organic predators of these viruses, bacterial wilts and diseases that we know about? Why hasn't anyone ever mentioned them before? When will they show up? How long will this take? I'm pretty old and I want to keep growing and enjoying my tomatoes as much as possible. In fact, I would like to have more each year, not less. I would worry that Mother Nature might not fix the problem while I am still around. Did she get the memo? She might not get around to it while I'm still here or even when my kids and grand kids are still around. What if she doesn't think it's a big deal or doesn't like tomatoes and doesn't bother to fix the problem anytime soon? What then? It sounds like an awesome solution but I might not get to enjoy the bounty of it! I don't like the sound of that!

“Challenges are what make life interesting and overcoming them is what makes life meaningful."

“The pain you feel today is the strength you feel tomorrow. For every challenge encountered, there is opportunity for growth.”

“There are no great people in this world, only great challenges which ordinary people rise to meet.”

I don't think I just want to sit around and wait for Mother Nature to fix 'Climate Change' either. She might not care so much that humans survive or are happy. I think we need to do our part too, just in case. Just saying..... I'll have to think about this some more.

Debbie Ann wrote:What an interesting idea.  “What would be the best way to breed tomato pests/diseases? Grow only tomatoes! Even more effective would be growing only one variety, or highly inbred cultivars bred in near sterile conditions.   What would be the best way to breed predators of tomato pests/diseases? Compost them 'non-thermophylically' (cool and slow), so as to breed the organisms that eat the problem organisms. “

I guess that's one way to fix the problem. I think that is probably the very best solution. Just let Mother Nature fix the problem. She's way better at doing these things than we are!

But that made me ask so many questions! Are there currently natural, organic predators of these viruses, bacterial wilts and diseases that we know about? Why hasn't anyone ever mentioned them before? When will they show up? How long will this take? I'm pretty old and I want to keep growing and enjoying my tomatoes as much as possible. In fact, I would like to have more each year, not less. I would worry that Mother Nature might not fix the problem while I am still around. Did she get the memo? She might not get around to it while I'm still here or even when my kids and grand kids are still around. What if she doesn't think it's a big deal or doesn't like tomatoes and doesn't bother to fix the problem anytime soon? What then? It sounds like an awesome solution but I might not get to enjoy the bounty of it! I don't like the sound of that!

“Challenges are what make life interesting and overcoming them is what makes life meaningful."

“The pain you feel today is the strength you feel tomorrow. For every challenge encountered, there is opportunity for growth.”

“There are no great people in this world, only great challenges which ordinary people rise to meet.”

I don't think I just want to sit around and wait for Mother Nature to fix 'Climate Change' either. She might not care so much that humans survive or are happy. I think we need to do our part too, just in case. Just saying..... I'll have to think about this some more.

I'm a similar situation. The area I had my tomatoes in (12 plants) was doing great in August to mid-September, the cherry tomatoes got to have 12-15 ft long vines and produced hundreds of fruit each, and the slicer tomatoes reached 6-7 ft with a dozen fruit each. But then late blight took hold and spread through the whole tomato patch and by early October, all the plants were on their death knoll. Eventually the tomato plants I had in more isolated locations got the same disease but it took another 4 weeks or so - I recon by that point it was getting too cold and the stress would've made the tomato plants susceptible to one disease or another regardless. But if all of those plants could've been producing for those 4 extra weeks, for a total of 10 weeks, rather than 6, that would've been great.

I also do not know what sort of predators might prey on these bacterial diseases. If the predators don't kill all the bacteria, I would think the plant will still die, and if they do then the predators die? It's not like with say, flea beetles, where these insects are generally non-fatal to the plants and you can maintain a stable environment with a moderate amount of flea beetles to ensure the predators have something to eat, but not so much as to overwhelm the tomato plants.

I'm still new to all this (this year was my first year growing vegetables and looking into permaculture) but I think next year, my approach will be to use a bit more determinate tomatoes (in a couple successions) to get big quick yields since my indeterminates didn't end up producing for much longer anyhow. Hopefully building my soil, composting and getting the planting times just right can also help get a yield faster and increase the harvest window. Maybe eventually my plants will be more resistant to these diseases, but I suspect it still won't be like with the insect pests where I have had success managing them with predators (flea beetles, aphids and hornworms were all kept to minimal levels by predation).

And as for the blighted plants, I'm just hot composting them and hoping that kills most of the diseases, but I don't expect it'll kill them all. Temps don't reach 100F here, it's rarely above 90F, so hot composting is more effective for cooking stuff.

By the way, the main diseases I've had issues with were late tomato blight, powdery mildew, bean rust, and cucumber beetle spread bacterial wilt.

Look up Charles Dowding on YouTube (https://www.youtube.com/c/CharlesDowding1nodig) and watch everything he says about composting - he puts pretty much all his blighted crops/roots/rubbish into his amazing compost.  We are following this methid, and next year we hope to start seeing the rewards.

I tried hot composting, but it's very cumbersome and in the end I found that it's not necessary for most diseased garden waste.

For example, the mosaic virus is very aggressive in my place.  It affects most summer vegetables but especially cucumbers. I don't like burning stuff because it's a waste of precious organic matter. So I put all the affected cucumber plants on a separate heap at a safe distance from the garden. Then I found that perfectly healthy cucumber plants grew from the special compost heap with diseased cucumber waste. The same goes for tomato rot, etc.

The only things I don't put on the regular compost heap are fruits with maggots or pupa of fruit flies and roots or things like couch grass that will grow underground. The fruits I burry in a hole deep enough to prevent the fruit flies from reaching the surface and the roots, couch grass, etc., I put in my bamboo grove where it's too shady for them to grow again.