Topic: Help needed for a cousin.

[tim]

An immaculate showing, I would say.  This is mid July, much better than mine!

By August "some form of mould which starts on leaves, spreads to stems, say half way up, and kills and destroys the plants. I try to contain by cutting off affected parts but once it appears I have not found a way of stopping it."

He does not recognise the symptoms of Blight to which I have referred him.

He waters by micro-bore into the saucers. His only feed is one dose of Chicken Manure.

Advice, please??

 

[growmore]

Tim,  I have seen  the same happen  with Toms watered in shallow troughs very similar principle.
My thoughts on this are there is too much humidity being caused by water evaporating from the  bare saucers /troughs.  Maybe he would be better with some deeper saucers with sand or ashes in as in a semi ring culture  type jobby.
Or watering with his microbore into the top of the pot  onto his growing medium . Then there is the importance of  the  ventilation  bit which I feel sure you imppressed on him .

 

[tim]

I'm with you on both those counts.

Wonder if there are any other ideas?

[Tee Gee]

Sounds like 'Grey mould' to me, probably brought on by fluctuating temperatures and humidity.

Are the drip feeds on all the time?

Why I ask is; they might be getting water when they don't want it and not getting enough when they do.

How I get over this when using the 'ring culture' technique (as this basically is);

I make a raised bed under the rings with a farm yard manure and compost mixture. This is a similar idea to what Growmore mentioned Ashes/gravel.

I always water this and only water the rings when feeding or at every second or third watering.

There is a picture of this at the end of this slide show; http://tinyurl.com/39hocg

Thats my view for what it is worth Tim, sorry I couldn't be of more help.

[Barnowl]

Aren't the pots a little small - could that stress the plant and weaken its defences?

[saddad]

Sound like grey mould, botrys(?) to me as well, mine start to develop it mid October..
 :(

[tim]

All MOST helpful. Thanks.

[calendula]

I was wondering whether the water is responsible - whether it is hard or soft, as there is some evidence that certain bacteria thrive better in certain water conditions but you'd have to do your own research on this as I am a bit hazy on it - just a thought 

[tim]

Good thinking there but, I believe, no problem when watering from the top. Waiting for confirmation on that.

[valmarg]

I agree with saddad, botrytis.

Looking at your cousin's plants, they are tied to canes.  What OH does is tie string round the plant and tie it to a cane that he has fixed across the top of the greenhouse.

I have noticed that where the ties go round the plant they can cause damage which let the botrytis spores in.  Like you Tim, once it occurs I cut out the affected leaves/stems.

I know I'm going to sound like the daft old biddy I am, but I wonder if providing a cushion between the plant and the string, ie a paper hanky, a bit of kitchen paper or cotton wool would stop the damage?

I think OH is going to have to give it a try next year ;D

valmarg

[Rob08]

Ditch the string and use old tights instead (or new ones if you don't know anyone who wears tights).  They are much softer, have more flex in them than string and won't damage the stems of the tomato plants.

[davee52uk]

Can you really grow tomatoes in such small pots? If so I'll try this and won't have to change the soil in the greenhouse.

[tim]

I don't, but can you not grow them in 9" pots? Cousin's are 12".

I would have thought that the bottom line would be 1/3 of a typical Grow Bag = 10litres??

[Barnowl]

I agree with saddad, botrytis.

 I have noticed that where the ties go round the plant they can cause damage which let the botrytis spores in.  Like you Tim, once it occurs I cut out the affected leaves/stems.

I don't think you are daft at all Valmarg. My plants had a similar pattern of infection and I reached the same conclusion this year but hadn't decided how to try and avoid it.  Was thinking of buying some "Soft Tie" but tights sound sensible.

I also wonder whether pinching out side shoots (not that there's much choice) and cutting back the leaves as the plant matures also provides entry points for disease.

If you go as low as 10 litres per plant, I suspect you'll really have to get the watering and feeding just right.

Some of my containers are small and those tomatoes were the most prone to bursting.

[tim]

Infection? Dust with Sulhpur afterwards?

Watering? Indeed - but the makers suggest 3 to a bag.

[tim]

I now note that Sulphur is only good for Powdery Mildew

Back to his 'handful of chicken pellets' - surely this is insufficient for the whole season?

[tim]

2 more queries.

1. Is not the make-up of multi-purpose compost much the same as that of grow bags - ie he needs no early feed?

2. Ventilation. Since most toms will grow outdoors, might it not be sensible to leave the doors of his 10x8 & 8x6 open 24/7?

[valmarg]

I don't think you are daft at all Valmarg. My plants had a similar pattern of infection and I reached the same conclusion this year but hadn't decided how to try and avoid it.  Was thinking of buying some "Soft Tie" but tights sound sensible.

Aw thanks Barnowl.

I also wonder whether pinching out side shoots (not that there's much choice) and cutting back the leaves as the plant matures also provides entry points for disease.

With regard to pinching out side shots, a lot of the tomatoes we grow are beefsteak, and it is recommended that the side shoots be removed.  We have never had very good crops doing this, and OH is a demon for surfing the net for advice.  He has been on a lot of American sites, and they recommend letting them grow, not pinching out.  Since following this advice we have had fantastic crops - a variety I would recommend is Mountain Pride.

I think I've made a right mess of this posting, but hope you understand what I was trying to say ;D

valmarg

[growmore]

Tim. I wondered if the watering system you showed was for convenience of them not being able to visit the plants regularly .. If so your idea of leaving all vents and doors open 24/7 once all danger of frost has passed  would make a lot of sense... Perhaps a fine screen mesh door type thing in the door ...
That way the humidity should be reduced quite a lot ..
Also there should be enough feed in MP compost for at least a month or six weeks After planting ..
I personally wouldn't use  just chicken pellets as these  are high in nitrogen which as you knows equals leaf growth and lush plants seem more susceptible to mould etc .Think they would be better with a more balanced feed as in BFB or GM. Then a high potash feed back end when fruit has set..
Just a thought Tim are the chippings in  the bottom of greenhouse stood on some kind of black polythene or on some type of porous stuff like ground cover?.
cheers Jim ...

[tim]

Yes Jim -  agree with the poor balance of poopellets. And fleece or such over the vents against airborne spores.

Good thinking about the flooring. I'll enquire.