I’ve got six tomato plants out on the terrace. A little while back I used a pallet to build a trellis for two of the tomato plants, and at the same time transferred them from there little pots into a much bigger shared pot. Although initially, everything was hunky-dory, since then they’ve been a little poorly and finally, I had to do some detective work and eventually diagnose Powdery Mildew.
As I set about trying to make my tomato plants happy again, here is a roundup of some of the leading tomato pests and diseases, and what you can do to prevent them.
These are the exact same chaps that love to attack your chilli and bell pepper plants. They are small clusters of insects on the stems or new growth, and in large infestations, they can cause quite an issue. Pinch off foliage where they are densely concentrated, making sure you throw those pieces into the rubbish and not on the ground. You can also use a diluted washing up liquid, to liberally spray the bastards! They hate the alkaline and will die off as a result, however you may have to repeat that a couple of times.
Blossom End Rot –
This is a disease that will take out your tomatoes and peppers. It is caused by a lack of calcium in the soil or drought, and manifests itself as a circular brown or black patch at the blossom end of the fruit. This can simply be avoided by regular watering, and not allowing the soil (especially in pots and bags) to dry out completely.
Blotch Ripening –
This is exactly what it says on the tin, and is when your fruits are blotchy and patchy when ripening. That is caused by irregular feeding and watering, and periods of overtly high temperatures. This can be avoided by regularly watering and feeding, and by ensuring that the temperature in your greenhouse or terrace doesn’t peak above 32°C, without adequate ventilation.
Foot Rot –
This is a disease caused by a fungal attack at the base of your plant. Think of it like athlete’s foot, but with tomatoes. Anyway, the best prevention is to make sure you rotate your crops, because once you’ve got it, there is very little you can do. The plant will wither and die, and that means no tomatoes for you.
Glasshouse Whitefly –
These teensy weeny white-winged flies will not just come after your tomatoes, they are also interested in your cucumbers too. The best way to get rid of them is the good old fashioned washing-up liquid solution, as the alkaline will kill them off, and leave your plant relatively unharmed. Other organic solutions include encouraging ladybirds into the garden, which will eat them all for you.
Magnesium Deficiency –
This disorder can affect almost everything, and occurs mostly when poorly drained sandy soil remains wet for prolonged periods of time. You’ll see yellowing of veins on the older leaves, and dead patches appearing alongside the yellow areas. The best way to get round this is to spray the plants with a solution of manganese sulfate (2tbsp to 11litres of water), and apply liberally. Give it a few days and it should have cleared up, but it not, repeat the spraying.
Powdery Mildew –
This is what I’ve got going on with my plants, and it’s a general term which applies to a who host of fungi that attack your plants. Best thing to do is remove all the infected growth, and burn it, and to plant resistant varieties. Fat lot of use that is now, but I think we’ll just have to see if our other tomato plants get struck down with it… I sincerely hope not.
Potato Cyst Eelworm –
These pinhead sizes yellow or brown cysts will appear any time from May to August, and they are hideous. They will cause wilting and eventually the death of your plant, and unfortunate the only treatment is to dig up the affected plants, burn them, and avoid planting on that site for at least 5 years. Nightmare…
Tomato Blight –
If you grow your tomatoes outside, you might find that you get this from time to time. You’ll realise that you’ve got ‘blight’ when a soft brown patch forms on the fruit, and then spreads rapidly. That fruit will then shrivel and rot, as the blight moves onto the next victim. All you can do in this instance is rip out the plant, and burn it. And although it is less likely to spread if you don’t crowd your plants, us lot with limited space don’t often have a choice, so make sure if you do see it, you remove that plant as soon as possible.