Latest posts by Gard

1 to 10 of 22

Tomato leaf problems - help

Posted: 24/07/2012 at 09:59
Morning! Italophile, I don't know if you've ever lived in the UK, but the weather is literally as changeable as the wind. Locally, today is set to be bright & cloudless, with a top temp of 23C. Tomorrow, cloudy & dull. Temp 18C. Next day, bright with heavy prolonged showers. Temp 22C. I have painted shading on the greenhouse (just a few days ago), but even so, at the moment (9am), the inside temp is 28C.

Around spring, when we had some decent weather, I decided to harden off some new plants, and placed them on the patio. A few hours later, all of the plants had severely scorched leaves. They survived, but looked ugly, until they grew a bit and I was able to remove the affected leaves. The lesson I learned, was not to leave young & tender plants in direct sunlight.

If it was in a greenhouse, Insomnia1973's spider mite problem could be resolved by keeping the air humid (according to the books). An alternative that I have used for most insect problems (aphids, black fly, green fly etc), that works a treat, is garlic tea. There are lots of recipes, but I take a whole bulb of garlic, crush the cloves with the flat of a knife and pour a litre of boiling water over the garlic, giving it a good stir to extract the essence. Clingfilm it and leave it until cold - the longer you leave it the better. Sieve it through several layers of kitchen roll to extract all of the bits, then pour it in to a 2 litre container (lemonade bottle is perfect), adding several drops of washing up liquid (not antibacterial) - this allows the tea to 'stick' to things (I.e. the leaves and insects). Top up the bottle with cold water. When you want to use it, give it a good shake, then pour into a small hand sized sprayer. Spray the affected plants, paying particular attention to the top tender shoots, and underneath the leaves. I usually spray the whole plant and any in the vicinity of the problem. This needs to be done regularly (every few days) until the problem is gone, and then keep checking for any new infestations. Do it early morning to allow the liquid to evaporate before the sun gets too hot and scorches the plant. When I first started using the tea I was greatfully surprised that it didn't harm the plants in any way, it didn't leave the lingering smell of garlic on the plants (just on my hands), nor did any edible plants taste of garlic. I hope this helps.

Tomato leaf problems - help

Posted: 23/07/2012 at 21:59
An update. Since my comments on 16/7/12, I have removed all of the badly affected leaves, leaving only the top healthier section. This seems to have stabilised the remaining leaves on all the plants (they are no worse). However there is no obvious new growth or sets.

I replaced a greenhouse tomato plant (the one with the dry set) with an outdoor tomato plant yesterday. I will keep you informed as to how they get on.

It has been suggested that temperatures for greenhouse tomatoes should not exceed 25 degrees centigrade. Yesterday, with the door and all of the vents wide open, new painted shading, and the greenhouse floor well damped down, it got above 49 degrees centigrade. Without installing insulation and air con, I'm unlikely to keep under 25 degrees. Any ideas?

My conservatory tomato plant started getting white spots over the lower leaves, but they were actual spots, not the blotches on Becks peppers. I cut off the affected leaves straight away and the problem seems to have stopped.

Something I have noticed with the very recent blaze of sunshine is that anything in pots, especially in a greenhouse or conservatory, start to wilt very quickly. The smaller the pot, the quicker they dry out. Large to very large pots are far less prone. Thus far I have managed to rescue several plants (giving them extra water) before they went past the point of no return. Be vigilant, but don't over water, and keep them away from a window. They will scorch if they are too close.

Tomato leaf problems - help

Posted: 16/07/2012 at 16:23

Thank you for the comments Italophile.

It would be interesting to know if I'm the only one having these problems, or if others are sharing my problems!

Tomato leaf problems - help

Posted: 16/07/2012 at 13:37
Not a good weekend.

Although I'm following all of the advice, the problem persists unabated. On some plants the more serious form of leaf problem is approximately 2/3 the way up the plant. Most of the leaves are now completely yellow and the worst are more brown than yellow, and are hanging limp. How much of these affected leaves should I remove? If I take too many, I might not have any leaves left.

On one of the tomato plants, although there has been a good growth of flowers, the flowers/petals have dropped off and have left tiny pinhead fruits on all of the sets. These fruits are not getting any bigger. Research seems to suggest that this is 'Dry Set'. The suggested cause is the air being too hot & dry. This plant is right next to the door, which has been left wide open every day, and as for it being too hot and dry - the only sunshine I've had is the wet stuff.

The plant next to this one has yet another problem - 'Blossom Drop' - the flowers are breaking off at the nuckle. Suggested problem - dryness at the roots and in the air - suggested remedy is watering regularly spraying the flowers.

My one large tomato plant in the conservatory - well away from all of the other plants - not only has 'Blossom Drop', but is also developing a nice collection of lighter coloured spots over the most of the lower leaves. I haven't discovered what that is yet.

The way things are developing, I will shortly be an expert on tomato problems, but not on actually growing them, as at this rate, it looks like I will not have a tomato plant left.

Tomato leaf problems - help

Posted: 11/07/2012 at 10:47

Re feeding the toms with Tomorite (or any other brand for that matter). I have only been feeding them once a week, at the recommended dose rate. If that is too much, how often should I feed them (bearing in mind that the outdoor toms, & one in the conservatory - as previously mentioned identical to those in the greenhouse - have been given identical treatment, without any problems)?

There is obviously something else going on - probably the mould you suggest - and I need a way to find out what. It's a mystery that I need to resolve, or it's likely to raise its ugly head again.

As well as spraying ES on the leaves yesterday, I also gave the greenhouse / conservatory toms a good soak (I used a mini watering can - capacity 0.7 litres - per plant. Does this qualify as a 'good soak'?), directly and carefully to the roots, without splashing. This is the first watering in 4 days. I'll check them again at the weekend.

I'll keep up a running commentary on what I'm doing, when, and any results - a sort of scientific experiment! Hopefully, this will help myself and others.

Thanks again,


Tomato leaf problems - help

Posted: 10/07/2012 at 10:10
Hi Italophile. Thank you once again for the info.

The compost mix, using a 1.5 litre pot, is in the following ratio:

2 x J. Arthur Bower's multi purpose compost.
2 x sifted garden compost (a mix of garden and food waste [potato peelings etc] fully organic - I don't use anything on the garden except on my pots - Miracle Grow, or Tomorite, used as per instructions).
2 x sifted basket compost (last years).
2 x perlite.

I also add in 2 scoops (about a teaspoon per scoop) of water retaining crystals.

I have used exactly the same mix on all of my pots & baskets (whether flowers or veg) and with the exception of the greenhouse tomatoes, I don't have a problem.

Just going out to spray the leaves.

Tomato leaf problems - help

Posted: 10/07/2012 at 09:26
Hi Italophile. There is still a mystery! My outdoor tomato plants (identical plants, compost, pots, watering, feeding etc, etc) don't have this problem - Why?

The article I mentioned above talks about using Epsom Salts to the soil, and later, as a foliar feed - doesn't mention if you can/should use both at the same time. Any ideas?

For soil treatment it mentions the amount of ES, but not if this is applied dry to the soil & then watered in, or applied as a liquid solution - if the latter, it doesn't mention what the mix ratio should be. Any Idea?

Tomato leaf problems - help

Posted: 09/07/2012 at 22:25
Thanks once again for the advice.

I was just flicking through the June 2012 issue of 'another large gardening organisation's magazine' - (I don't know if mentioning the name of the organisation/ magazine is an infringement of some kind, so I had better not use them) and on page 2x there is a picture of a tomato leaf affected by magnesium deficiency. It is identical to the leaves on my tomato plants during one stage of this progressive problem. So thankfully, I at least know for sure what the problem is.

Tomato leaf problems - help

Posted: 09/07/2012 at 15:24

Thank you once again Italophile.

Great news re the PH level.

I guess I'm hedging my bets with my 'plan of action', i.e. using your advice to treat a possible fungal infection (esp re ventilation), and the epsom salts for the suggested magnesium deficiency - hopefully, it can't hurt?

 Re spraying for fungal infections, what do you spray with, when, how etc, etc?

Tomato leaf problems - help

Posted: 09/07/2012 at 14:22

Hi all!

I checked out the website that Bob suggested (Cladosporium Fulvum - leaf mould). The leaves on my tomato plants, especially the recently affected ones, don't show the same signs as those of Cladosporium Fulvum. Using a magnifying glass, they only have tiny brown dots on the top of the leaves and are totally clear underneath. In fact the more advanced leaves don't show anything underneath until the dots have formed into large clusters and the tops of the leaves start yellowing.

Re the ventilation, as mentioned previously, I have two atuomated window vents, as well as a ground level louvre window, and of course the door, the latter two of which are opened fully every day, and I can see the circulation wafting the leaves of the greenhouse plants.

The greenhouse is also planted in THE sunniest part of the garden, and has a good clear area around all sides. 

I have contacted the helpline of another very large gardening organisation (I joined at GW Live), who, on being directed to the photo's on this website, stated immediately (and again, following consultation with a tomato expert) that the problem was not an infection, but is a deficiency in magnesium. They advised treating the plants with epsom salts every two weeks, until the problem clears.

A suggestion for the possible cause, was that I created my own potting mix (following an article in GW), and that the PH balance / nutrient level (and other things that I forget) is not perhaps what it should be, and in future, to use new ready made compost for any vulnerable plants like tomatoes.

I have since carried out a number of their suggestions to test for potential problems:

(1) Test the soils PH - in my case the soil test kit indicates a PH level of 6. The same kit suggests a PH range of 5.5 to 7.5 for tomatoes. I am therefore towards the acidic end of this range, but still within parameters.

(2) Check that the root growth is OK. My tomatoes are planted in purpose made plastic rings (the retail version of a large pot without a base), sited on the top of the larger growing pots. I checked the roots within the plastic rings and the larger pots. I was amazed. There is a massive, dense, healthy looking root system that goes down to at least 6" below the plastic rings (as far as I could get down into the pot), with no sign of water saturation.

Following all this advice (thank you all!), my plan of action is to follow Italophile's (a), (b) and (d) - the greenhouse is already in the sunniest spot, so not (c) - as well as his excellent watering advice, plus persevere with the epsom salts, and of course next year, not to use my own potting mix.

I will keep you up to date with the progress.

With all this talk of possible fungal infection, I forgot to ask, what do you do at the start of the season to limit the likelyhood of such an infection in the greenhouse?

Many thanks once again.

1 to 10 of 22

Discussions started by Gard

Tomato leaf problems - help

Curling, mottling & yellowing of leaves 
Replies: 91    Views: 29136
Last Post: 20/08/2012 at 11:24
1 returned