I used to grow amazing tomatoes. One year, one grosse lisse plant yielded 57 kilos. From the following season onwards however, every type that I try to grow starts off okay, but after it grows to about 18", the leaves start to go yellow, then brown and papery. I can harvest a few fruit off each plant, but the plant is extinct by the time they ripen. I have tried growing them in potting mix in big pots, but the same thing keeps happening. I live in coastal NSW, Australia where we have a warm temperate climate. I don't have a photo of the problem plants, but I do have one of the amazing grosse lisse plant that we grew. I don't know how to add an image from an iPad anyway.

My first thought was "soil disease" when I heard that you had good crops up until a certain year, then plants started dieing young. One possibility was roots dieing young, then the plant drying out and dieing.

If you cleaned pots and garden tools really well before starting plants in pots of potting mix, that SHOULD rule out soil diseases. Possibly mixing potting mix in a wheelbarrow and with a shovel or hoe that had soil on it could spread a root disease.

Was there any source of contamination between old tomato beds and new pots? I'm guessing that soap and water might not be enough. Chlorine bleach or hydrogen peroxide might be needed IF some hardy soil microbe is the villain.

Can soil pests like insects climb into pots?
Can microbe spores in soil be blown with dust into pots?

Is the climate suddenly so much hotter and drier that there's no way to water them enough? It sounds as if you are used to HUGE plants that need root systems like the NYC subway tunnels.

Do you irrigate with town water, and the town water supply was recently "improved"?

You might try another crop in pots, or in some spot in your yard as distant as possible from any bed where you grew them for years. Maybe the tomatoes in the ground died for one reason, and the pot tomatoes died for a different reason.

It doesn't sound like an 18" plant could already be pot-bound or root-limited, but I imagine that any plant that could produce 57 kilos in a year would need a 10-20 gallon pot, and/or being watered twice every day and fertilized weekly.

I'm just guessing, really.

Thank you for the prompt reply.
Firstly the whopper crop came from a normal gross lisse plant that just went on and on cropping. I had it espaliered along a north facing fence and it was not typical of the size of our crops, it was outstanding, although we always had very good harvests in general.

Can't say that I was particularly hygienic with the garden tools, but didn't need many because we just emptied the bags of mix straight into the pots, and planted them with our hands. However the plant tubs had been used before and not sterilized.

We have tried spots in different locations all over the garden. How do I go about sterilizing with chlorine bleach? Doesn't it alter the ph? We have improved sandy soil and live between a lake and the ocean. Soil ph is always around 7.

Irrigation? Now that's a good thought. We irrigate with a shallow bore (11 feet down) that we have been using for 30 years. I have found that beans that are usually prolific are struggling now. Maybe the bore is going salty. It tastes fresh though, and the gold fish don't have a problem with it, and the waterlilies are like trifids. No other plants appear to be suffering except I just remembered that two potted raphis palms suddenly died for no reason last year. I blamed stray cats using them as toilets.

Anyway, thank you so much for you educated and considered reply. I will have to somehow try to plant a tomato somewhere where I can try town water on it. We have the best tasting town water of anywhere that I have ever been.

Tomatoes are prone to blights. Both Early Blight and Late Blight. Sounds like you have one of them. They are blown in the wind and I don't know what you can do if its Late Blight. If early blight try growing some disease resistant varieties.

I hope one of my guesses gives you a helpful idea !

>> How do I go about sterilizing with chlorine bleach?

I meant that cleaning pots only removes most of the soil, so many people soak them in bleach after cleaning as far as practical.

The recipe I heard was to soak pots for 10 minutes in 1 part supermarket "chlorine" bleach plus nine parts water.

But I don't know what concentration that assumes about supermarket bleach. Look for "hypochlorite" or "chlorine bleach", not "oxygen bleach". The newer "oxygen bleach" doesn't kill microbes as well.


>> Doesn't it alter the ph?

I would use chlorine bleach to sterilize pots or tools but definitely not on soil.

I think the only way to keep a bed relatively free from cumulative soil diseases is to use rotations or discover what soil conditions favor that disease and somehow change the conditions. Improved sandy soil sounds like fast drainage and probably good aeration.


I was wondering about ocean salt water getting into your water table. Like, in the soil near the roots, since you wouldn't taste it there. Experimenting with town water might show something, especially in pots or deep raised beds.


A plant disease like blight sounds likely. I guess long rotations wouldn't help much if spores blow on the wind.

It might have gotten worse suddenly just in your yard or throughout your neighborhood, or county-wide. Asking some neighbors if they used to be able to grow tomatoes might turn something up.

Your local cooperative extension office probably has websites that would discuss your regions' most common diseases of each crop. (There's a link to a coop-finder site in my signature block.)

Thank you for your continued suggestions Rick and Rita. I have tried so many so called "disease resistant" tomatoes and all had the same problems. I think now that my last hope will be changing to town water, and if that doesn't work, I will have to assume that the problem is a soil or wind blown virus, and give up. I was wondering though, are beans susceptible to tomato viruses? I know that nematodes can invade them both, but I have checked for that, and there have been no lumps on the roots at all. You are right about our soil, it is very, very, well drained, and needs heaps of water, which it gets.

I will ask around. You may not realize that I live in Australia, so your co-op finder site wouldn't apply. My neighbors are not gardeners, nor is anybody that I know living locally.

Best of luck, Joan! I didn't realize you lived in Oz.

There are several ATP members from NSW, maybe they could make a suggestion if yours is a regional problem.

http://garden.org/users/member...

MatthewWilliam Sydney 76
Chrissy100 rural Sydney Australia 76
sjw282 St. Clair, NSW, Australia 91
bree North coast NSW Australia 111
alleciaward Orange, New South Wales 187
Handed Northern Tablelands NSW Australia 191

You can draw someone's attention to a thread by preceding their ATP screen name with an "@" sign like this: @bloomlover.

Have a happy New Year and good luck with the tomatoes!

If you were a southern USAin, I might wonder if you were being visited by root-knot nematode.

To stick with that presumption, the cure would be lots and lots and lots of compost. Every year, year in and year out.

Thats not true (your geography) so my cure might not suit the tenant at all,

Well, adding compost to your veggie beds is always a good idea as veggies, especially tomatoes, love lots of compost.