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Latest posts by Italophile

Tomato leaf problems - help

Posted: 08/07/2012 at 17:07

Spot on, Bob - and I use the term advisedly in light of Gard's problems - humidity is an invitation to fungal problems. As is any sort of moisture on the leaves, especially overnight. It's always best to water in the mornings.

I helped a friend just outside Cortona set up her vegie garden. She installed an overhead sprinkler system. I told her she was in for trouble. Sure enough, her tom plants - and quite a few other things - are plagued by fungal problems.

Also, fungal spores can and will drop onto the soil under a plant and can be splashed back up again when watering. I maintain a gap of about a foot to 18" between the lowest foliage and the soil to help guard against same.

Tomato leaf problems - help

Posted: 08/07/2012 at 13:07

Gard, I think it's probably one of the Leaf Spot diseases, and Dove might be onto something with the added deficiency problem. As I said earlier, there's nothing you can do to treat fungal problems once they're established. You can only remove foliage, trying not to remove more than about 30%.

Apart from that, I'd cut back on both the watering and feeding. To hark back to the watering situation: regular watering just means watering to a pattern and the pattern is dictated by the plant's needs. Simply, if the mix is damp, the plant doesn't need water. The trick with containers is to poke your finger as deeply into the mix as you can. The surface might appear dry, but it's the first thing to dry out, along with the outer edges of the mix. So test the mix as deeply as you can towards the middle of the container. Any dampness at all means water isn't needed. Continually watering already damp roots just means a plant with wet feet and few plants - least of all toms - prosper with wet feet. If it takes three days for the mix to dry out, regular watering, in your case, would mean every three days. And, when you water, water well. Then let the mix dry out again. And so on. I have to say I would be enormously surprised if a container that size, in that position, needed water more than every three days. Look at the example of my neighbour's plant - in a container, in 6 hours of direct sun, with the temps around 35C - not needing water more than every two days.

Cut back the feeding to once a month. Dove is right in that potassium-rich fertilisers can impact on the mix's nutrients. And the simple fact is that toms don't need that much fertiliser. As I suggested earlier, an over-watered and over-fertilised plant isn't a happy, healthy one. It's bloated and vulnerable. Less is much preferable to more in terms of both water and food.

Change the regime, give it a few weeks, and let's see how things look.

Tomato leaf problems - help

Posted: 08/07/2012 at 10:50

No, they look like pretty classic disease-based lesions. It's a matter of which one. For example, Early Blight lesions are made up of lots of little concentric rings. Septoria Leaf Spot's lesions have wee tiny spots at their centre.

It's also rare for a tomato to suffer from deficiencies once it's established. It would have to be the poorest of very poor soils to lack, for example, enough magnesium. Deficiencies mostly occur when the plants are at the early seedling stage and growing in sterile or very basic potting mix.

Tomato leaf problems - help

Posted: 08/07/2012 at 10:08

No, there are definitely lesions on the leaves, particularly in the photos of the plant. The photos of the removed leaves show whatever it is has progressed. Magnify the photo and you can see very crusty lesions on the edges of the leaves in the second of the removed leaves photos. It's hard to tell some of the fungal diseases apart without a very close look at the lesions themselves. Even magnifying the photos isn't showing the image clearly enough.

Gard, can you have a good look at the lesions - those individual brown spots, like blisters - on the leaves? Check whether they have a light halo around them? Whether the blisters themselves are made up of concentric rings? You might even need a magnifying glass. And is there any sign of damage to the plant stems?

If it is fungal, and I think it is, all you can do is remove the affected leaves. Spraying doesn't help once the problem is established. Spraying is only useful as a preventive measure. Fungal spores are everywhere in the air, it's virtually impossible to avoid them. Unless you spray preventively, all you can do is provide plenty of air circulation and avoid getting the leaves damp or leaving them stay damp.

Tomato leaf problems - help

Posted: 08/07/2012 at 09:36

Gard, check my post just above your last one. Your problem, in this instance, isn't over-watering. It's disease. I'll get back to you on it. And your follow-up questions.

Tomato leaf problems - help

Posted: 08/07/2012 at 09:03
Gard wrote (see)

Hi All. Went to my greenhouse this morning and the problem has worsened. In various stages, it's near to the top of the plants.

I have taken off some of the worst affected leaves and taken photo's of the same, which will hopefully be attached


. Can anyone give me a definitive answer to what the problem is, and the most expeditious remedy.

 N.B. I have two other identical tomato plants, planted exactly the same way (compost, tubs etc) outdoors. Other than the fact that they are slightly less advanced than those in the pictures, they are in perfect health, even after suffering the almost daily deluge of the past few months. The only difference is that God is watering them, not me.

Gard, that's not a watering problem. It looks either fungal or bacterial. I'll get back to you, but, in the meantime, if you can, move the affected plants away from any healthy ones nearby.

Tomato leaf problems - help

Posted: 08/07/2012 at 08:58

That's odd. It missed the last bit of the post. Maybe the software got bored with all the words.

Anyway, here's what was missing:

It means establishing the plant's requirements and watering - approximately the same amount - accordingly.

My plants, in the ground, in (obviously) the same weather conditions as Ettore's plant, are watered every four or five days, very very very deeply, driving the roots down deep into the soil for their moisture, away from the heat of the surface soil. And they love it.

Sorry about writing a book.


Tomato leaf problems - help

Posted: 08/07/2012 at 08:28
sotongeoff wrote (see)

Why are you watering them so much-this is the problem-there is a tomato expert on this forum-italiophile-who constantly says they need tough love to grow properly.

Easeback on the watering-let them dry out-remove some of the yellowing leaves -only a few -not all and they will be fine

Just not so much water.

Geoff is right. The biggest mistake you can make with toms is watering by rote - automatically, regardless of conditions. The rule of thumb is simple: water toms when they need it. When do they need it? When the mix - in the case of containers - dries out. You can let the mix dry out. It will not hurt the plant. Leaving the mix dry for a week obviously will hurt the plant but over a day it won't.

There's a myth that toms are delicate plants. They're not. By nature, historically, genetically, they're tough, robust individuals that will survive in adverse conditions. Watering a tom in a container once a day - let alone twice a day - amounts to overwatering. Here's a case in point -

Every year I give our (now) 8 year-old neighbour, Ettore, a tom in a pot. He loves gardening, he watches me from his window in my orto (vegie garden) and, one day, wants to help me. His care for the tom amounts to counting the fruit. His mum, Paola, does all the work. This year it's a Camp Joy (aka Chadwick's Cherry) cherry in a relatively small container.

Now, they have no garden at all. The plant lives outside their front door. It gets about 6 hours a day of full sun. And the temperatures have been in the mid-30s for the last month. Paola waters her window boxes every day. I've had almost to break one of her arms to stop her watering the tom every day. Even 6 hours a day of direct mid-30s sun doesn't completely dry out the mix in a day.

She asked me why the leaves were yellowing. I told her the roots were constantly damp. She was over-watering. I told her that toms aren't flowers in a window box. They're a different beast with different requirements. I got her to stick a finger deep down into the mix. Sure enough, deep down, where the roots are, the mix was damp.

Finally, I've got her watering every second day. The yellow leaves are disappearing and the plant is starting to fruit.

Many of the problems that arise for the home tomato grower come about when the plants' natural sturdiness is overwhelmed by pampering - over-watering and over-feeding. Pampering a tomato plant doesn't strengthen it. It weakens it. An over-watered and over-fed plant is more vulnerable to disease and other problems.

In simple terms, producing fruit is a plant's means of reproducing itself. Tomatoes will feel more inclined to reproduce themselves if they feel ever so slightly threatened. It's their inbuilt survival mechanism. That's what you need to exploit to maximise production. Call it what you like - tough love, controlled neglect - but it's the exact opposite of pampering.

As lilylouise rightly says above, irregular watering is thought to be one of the factors contributing to Blossom End Rot - no one actually knows for sure - so the watering pattern needs to be regular. That doesn't have to mean every day. It means establishing the plant's requirements and watering - app

Advice on repotting my tomato plants please.

Posted: 07/07/2012 at 08:01

I'd plant into normal compost and fertilise separately. Bearing in mind that (a) toms don't like overly rich soil; and (b) don't need a lot of fertiliser. It's a common tendency to pamper tomatoes with lots of water and fertiliser. In fact, they will perform better - produce more fruit - if made to struggle a bit. "Tough love" is the go. Fertilise when the first fruit appears, then - if the roots are confined, as in pots, etc - no more than once a month afterwards. Mine, in the ground, are fed a couple of weeks after planting out, again when the first fruit sets, then only once more later in the season.


Posted: 06/07/2012 at 17:35

Sounds like too much water to me. It would need to be pretty warm for toms in the ground to need water every two days. Heck, it's in the high 30s here, the toms are in full sun, and I don't water mine more than once a week. But very very deeply when I do water.

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