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Every year I try to grow tomatoes - and every year they succumb to illness. I have 3 plants in 11 inch pots in a mini greenhouse, and 2 in the same pots outside on the patio.
Every year previously I have bought plants but this year they are grown from seed - 'maskotka'. As soon as I spot diseased leaves I take them off and spray the plant with a washing up liquid, bicarb and water mixture, but this time it seems to have spread to all the leaves despite this. They have been given liquid feed, and I used fresh compost. What has worked for you, and what varieties do you recommend for disease-free plants? Thanks
Are you spraying the fetiliser or bicard on the leaves, this causes problems. Alicante and Moneymaker are good old favourites, never fail. But saying that if you have tomato blight it is hard to get rid of, it is airborne and can hang around for years.There are all sorts of problems with tomatoes, the weather, too hot too cold, over watering, fly and ants. As soon as the first truss appears you can remove all leaves, below, if the plants are badly infested and trusses have formed remove all leaves and burn or dump do not compost. Keep trying
Thanks! I'll try taking the leaves off and will hopefully get some tomatoes. Previous attempts have been at a different house. I'll have a look at the varieties you mention. The fertiliser was just going on the roots, but I was spraying the leaves with the home made remedy - it's supposed to stop fungal things spreading but I'm not convinced it helps.
A couple of things, bookmonster.
First, spraying against fungal problems has to be preventive - ie, spray before the fungal spores arrive. Once they're in situ, with symptoms showing, spraying is a waste of time. All you can do is remove the affected leaves to try to minimise the spores' spread.
Second, your spray recipe isn't going to help even if sprayed preventively. It's claimed by some that bicarb can alter the pH of the leaf surface to create an environment unsympathetic to fungal spores but the evidence is entirely anecdotal. There's no scientific evidence to support the claims.
About the only available* spray that has been proved scientifically to help against fungal problems - if sprayed preventively - is one of the copper sulphate products. They're organic and they used to be every tomato grower's best friend until concerns were raised about (a) copper being a metal capable of building up in the soil; and (b) its impact on foraging insect life.
*The very best spray against fungal problems is a chemical that, to my knowledge, isn't available to the domestic market in the UK. Unlike in the US where it's widely available and very widely used even by many organic growers such is the product's otherwise benign properties and qualities.
Unfortunately this site's photo software is playing up again so I can't get a good, close look at your plants. Any chance of some closer photos?
The second photo seems to show a fungal problem. The pale leaf colour, though, could be a nutrition issue. Are you using commercial potting mix or home compost?
Thanks for your reply Italophile! Useful information to have. I wondered about a deficiency. They're in commercial multipurpose compost and have had 2 doses of liquid feed - the first a cheap commercial tomato food, the second seaweed extract in case the tomato food was lacking anything.
Unfortunately I have now snipped the discoloured leaves and don't have any more pics. A lot of the tips on the outside ones (2nd photo) were also black and shrivelled. The ones in the little green house weren't as bad as I thought at the top.
Some commercial potting mixes are better than others, bookmonster. You get what you pay for. The cheaper it is, the more rubbish it is. But a top quality mix will have more than enough of the right basic nutrients for the plant not to show signs of deficiencies. How would you rate your mix?
Shame about the lack of evidence. All you can really do is keep a watching brief and post more photos if the need arises.
I will do, thanks! It's a decent peat free compost, not really cheap or expensive.
Out of interest, bookmonster, what's the pH of the compost? If you still have a bag, the figure should be listed on it alongside the ingredients, etc. Some peat-free composts have a pH higher than toms really like.