Topic: Heartbreak tomatoes

[Garden Manager]

No not a new variety, but what my 'sub arctic plenty' bush tomatoes did to me this year. Broke my heart!  :'(

They were going so well and producing a large crop, when the dreaded blight struck them. I spent a difficult morning yesterday cutting down and getting rid of the plants, while trying to save as much of the fruit as i could. Unfortunately the crop was only just starting to ripen, so most of the fruit are green. I have saved the cleanest to try and ripen them 'off the vine' but I am not holding out much hope.

It just had to happen to the plants with the biggest crop on didnt it? I have cordon types nearby, seemingly unafected, but with a much smaller crop. I wouldnt have minded so much if they'd been blighted!  :(

[aquilegia]

Poor Richard - big hug to you. It's horrid isn't it.

I've been quite successfully ripening toms off the plant - quite a few have been knocked off by the wind or not very careful handling.

I put them on a plate (or tray if there are a lot) and pop in a ripe banana, then cover with a clean teatowel and leave on a window sill. Check daily in case any go funny (especially where touching the plate). it works, so don't panic.

[Bionic Wellies]

I read once that if you bung the green toms into a dark drawer and leave them for while (couple of days or so ) they will ripen just fine - and it does actually work - I d loads of green toms from my hydroponics system at the end ofthe season and the majority ripened off in a drawer.  Te rest ended up in green chutney.

[Doris_Pinks]

If it is any consolation Richard, I have thrown away pounds and pounds of fruit because of the blight, so I shall weep with you! Have to say tho, my yellow Tomato fruits do not seem as affected, even though the plants themselves have been showing signs. DP

[Garden Manager]

Do they need to be in the dark to ripen off the vine?  I have mine hung up on a string in the greenhouse. Full light but not direct sun.

Dont worry, some will be made into green tomato chutney!

[Macca]

I'm still in a bad mood after pulling up about 10 plants this morning, i salvaged what i could and will get some chutney on the go. But can  somebody confirm that what i have is blight from the attached picture. Is it due to the wet weather we've had or just bad luck?

[Garden Manager]

Macca, thats definetly blight you have there, know it all too well. When i first spotted it on my toms, it tied to ignore it, tried to pretend it wasnt blight, but of course it was  >:(.

It is the weather i think. Blight thrives on warm wet conditions which is what we had in August. I got it last 2 years ago when we had, had a damp spell in the summer. Last year fine, ideal for tomatoes rather than blight  ;D.

Funnily enough though, i have tomatoes still groing , in pots in the same place they were when i got blight last, but this time they have been unaffected. it was the others growing in the veg plot proper that caught it.

There is sadly no cure other than to destroy the plants and bin them (dont compost). And little prevention, other than not growing tomatoes outside.

[Doris_Pinks]

This makes for interesting reading.......I am still weeping over my lost Toms! :'(
http://www.hdra.org.uk/factsheets/dc17.htm

[Hugh_Jones]

Just a couple of points on the ripening of green tomatoes, whether on or off the plant:-

(1) The question of light or dark does not matter very much - whether you leave them in the light or keep them in a dark drawer they will ripen at the same speed

(2) If you want RED tomatoes temperature DOES matter.  The colouring of ripe tomatoes is governed by the ratio of two chemicals, carotene (yellow) and lycopene (red). Lycopene is not produced at temperatures above 80 deg F, while carotene is.  The optimum temperature for best red colouring is about 75deg F (75 - 80 deg F is also the optimum temperature for photosynthesis, so that gives two reasons for not allowing your greenhouses to overheat), so if the fruits are allowed to remain in hot sunny conditions for two or three days the carotene (yellow) will develop for 24 hours each day, while the lycopene will only develop when the temperature drops.  The result, inevitably is that the fruits will never develop the full red colour but will remain an indeterminate orange and possibly patchy colour

[Mrs Ava]

That is very interesting Hugh, and I shall keep an eye on the heat in my greenhouse from now on.  I assumed that it needed to be nice and hot to get the toms to go red, so have been keeping the door half closed during the day to keep the temp up.  As for my green casualties that I knocked off, I shall keep them in my warm kitchen with the ripe banana and hope they redden up a bit.

[Jill]

Well, that explains why my few unblighted toms on the sun-soaked lottie only managed orange and since bringing into the kitchen have turned a beautiful shade of red.  Thanks, Hugh.

[tim]

Much sympathy, Richard. My leaves are just showing the first signs - indoors. Strangely, the topmost ones.

Hugh - that's useful - filed. We learn every day. Does the same apply to peppers? And if you have an oven for a greenhouse, you should grow yellow toms?

Emma - heat? Why do I rabbit on about having 24 vents?? And still it can overheat! = Tim

[aquilegia]

I've been blighted too. A lot of the plants have had suspect leaves, but I found two with blackened stems yesterday, so ripped them out. I have four dinner plates covered with green toms waiting to ripen (interesting stuff there Hugh!)

If I put the blighted plants in black sacks to cook into compost will it kill off the blight? I hate binning green stuff.

[Garden Manager]

I've been blighted too. A lot of the plants have had suspect leaves, but I found two with blackened stems yesterday, so ripped them out. I have four dinner plates covered with green toms waiting to ripen (interesting stuff there Hugh!)

If I put the blighted plants in black sacks to cook into compost will it kill off the blight? I hate binning green stuff.

I think most compost bins we home/lottie gardeners have dont get hot enough to kill the blight spores. Thats why they say dont compost blighted plants. Best either burned (dont like burning) binning (our council doesnt collect green waste) or taking it to the tip. Most councils put green waste on one huge compost heap which gets realy hot (I guess hot enough to kill blight spores), so if you get rid that way you are still recycling the material, just not for your own use..

I know its hard, but you dont want to risk reinfecting the garden for next year do you?

[aquilegia]

Richard - I wasn't talking about putting it in the normal compost bin, but in a black bag to leave in the sun to cook, so I guess if a huge heap's heat would kill it, the black bagging would. Anyone?

[Doris_Pinks]

Aqui that hdra factsheet says
" Remove potential sources of infection - try to harvest all tubers, even the tiniest, so that there are none to regrow next season. Never abandon old tubers around the garden or allotment, or try to compost them - they are best burned, put in the dustbin, or buried deeply (over 60cm/ 2ft). It is probably wise not to compost tomato fruits either. Infected potato and tomato haulms (foliage) may be composted in a good active heap. The likelihood of resistant spores being present is very slim. Infection is much more likely to come from external sources"
 So I have composted the foliage and dumped the fruits.

[aquilegia]

Hooray! Thanks DP. I cannot bear to throw away potential compost.  :D

[Hugh_Jones]

tim, shame on you.  If you have an oven for a greenhouse you should cool it, and the way is not just by ventilation but by water evaporation.  Many years ago I evolved a mechanical method (which worked) of doing this by attaching a self-opening vent mechanism to the specially lengthened handle of the spigot tap on my water butt and running a perforated hose along the concrete path of my greenhouse. The mechanism was set to open at about 80deg F, and 2 gallons of water evaporating was sufficient to lower the temperature of the house by about 5deg.

Sorry I can`t help about peppers - I only grew green ones.

As to yellow toms, the only time I ever grew these (Golden Sunrise which I grafted onto F1 stocks for extra vigour) my family refused to eat them because "they don`t look right", but I believe that the only essential difference genetically between the red and the yellow is that the yellow don`t produce lycopene, so presumably the temperature is not a factor in the colouring.  However the temperature is still important in the matter of photosynthesis so it isn`t wise to simply let them cook.

[Garden Manager]

Richard - I wasn't talking about putting it in the normal compost bin, but in a black bag to leave in the sun to cook, so I guess if a huge heap's heat would kill it, the black bagging would. Anyone?

Not really sure. Might do, but no guarantee it'll get hot enough.

Does anyone know the temperature required to kill blight? Hugh? John Miller? anyone?

[Hugh_Jones]

Sorry to be so late in replying to this one Richard - I hoped John would get here first.  I`m afraid I cannot quote any actual temperature required to kill potato blight, but can only refer you to the tables I have for soil sterilization:-

130 degF     Weeds, earthworms, eelworms
160  "          Wireworms, bacteria & non-spore forming fungi
180  "          Nearly all viruses & fungi
200  "          Tomato mosaic virus

The normal recommendation for soil sterilization, of course, is for a minimum of 20 minutes at 210 degF

The highest temperature I have ever recorded in my (very active) compost is 140 degF, using a balanced mixture of lawn mowings, weeds with soil on their roots, vegetable refuse, and solid 1" timber bins.

I would also add that I recently stacked a large load of fairly fresh cow manure (with straw) in an enclosure and covered it entirely with black plastic.  The temperature reached 130 degF but as soon as it started to cool the whole surface (under the plastic) became covered with a growth of white mushroom-like fungi (which I`m still trying to identify), which had obviously survived the heat without difficulty.

Personally I would never put fungi-ridden matter in my compost bins.