Organic Gardening

greine

Hi Everyone, I'm just wondering if any of ye boarders have good tips on organic gardening? In particular, what could I use on my spuds to prevent blight? I have every farmer telling me if I don't spray with dithane now my spuds will rot! I have a smallish garden and grow some fruit and veg every year, and have managed to avoid pesticides and chemicals so far but this is my first year growing spuds, so I'm not sure what risk the blight poses (no, I don't remember the famine) and I'm not too keen to introduce chemicals into my little patch, any suggestions?

Thanks, G.

beer enigma

Not easy - I have a 70ft sq 'allotment' area at the end of my garden and grow all of my own veg organically - best tip I can give you is to go for the early varieties as they generally avoid blight.

There's a good paper on organic spuds here

http://www.redepapa.org/ware.pdf worth a read - see page 20 onwards for blight.

greine

Thanks for that, Andip, wow,there's a lot that can go wrong! At the moment there is no sign of blight on my potatoes, so maybe I'll be lucky..but I still have a month to go! G.

Gordon Gekko

I wouldn't worry about blight - if you notice it on the leaves, you still have time to cut down the stalks (and dispose of them either by burning or in the rubbish - don't leave them lying around) and the potatoes should be fine, if a bit small. Particularly if you grow tomatoes or aubergines, you should cut the potato haulms (stalks and leaves) at the first sign of brown/black blotches on the leaves, as blight will infect toms and aubergines also (they're part of the same family as potatoes).

You could escape it anyway - I haven't had it in the two years I've grown spuds - didn't bother growing them this year, they take up too much precious space!! I grew a blight-resistant variety last year, Sarpo Mira, which was great. Also, as Andip says, early potatoes tend to escape it (potatoes come in two main groups, earlies and maincrop).

Even if you lose your entire crop, it's not the end of the world - certainly not when the alternative is spraying dangerous chemicals!

The Organic College

Bluestone and Washing Soda mix.

Add 30 g Bluestone (copper sulphate) to 2 litres of hot water.
In a separate container add 40g washing soda to 3 litres of hot water.
After a half an hour mix the two liquids and spray directly onto the potatoes, making sure to spray under the leave as well.
This 5 litre mixture is enough for 20 square metres.
Organic gardeners are permitted to use bluestone (copper sulphate), but certified growers must get permission from the organic certification authorities before using the spray.

Spray for Prevention of Insects on Cabbage

Break a clove of garlic into a litre of hot water. Add a spoon of washing liquid.
Mix them together and pour through a sieve.
Spray the mixture directly onto insects every day.

djsilver17

Organic College, where can I find Bluestone in Cork?? I've been ringing around Garden Centres, DIY and Hardware stores but no one has any idea what I'm talking about. Next step ringing pet stores as I understand copper sulphate is used to clean aquariums. Suggestions please, please, please!

Also, is it safe to use the Bordeaux mixture on tomatoes as well as spuds? Should you avoid spraying right onto the developing fruits?

Thanks.

UPDATE: Lots of ringing around, found some. 1kg bags of Bluestone for 6ish euro at the Dairygold CoOp Superstore in Carrigaline Must be the only freaking place in the city that carries the stuff.

The Organic College

Hi djsilver17
If you know a good chemist shop they should have it there. You can always link in with our facebook page and anyone there from the Cork area should be able to help you with the name of a chemist shop that sells it.

The Organic College

Is your garden open or is it sheltered? If its open then you have less of a chance of getting blight. The more air and sunlight that can get at it the better for all your veg. Regarding blight.. i am afraid if its in the area you wont be able to avoid it. the best you can do it to spray for it using Bluestone and Washing Soda mix. When you are spraying it on make sure you get the stalk and the underside of the leaves then the top of the leaves, blight will attack any place that has no spray on it. If you haven't used this mix before be careful in using it. Make it up in two separate containers and only mix before you are ready to spray. Your potatoes will have to be sprayed three times. It is IMPORTANT that you spray in dry weather.

Bluestone and Washing Soda mix.

Add 30 g Bluestone (copper sulphate) to 2 litres of hot water.
In a separate container add 40g washing soda to 3 litres of hot water.
After a half an hour mix the two liquids and spray directly onto the potatoes, making sure to spray under the leave as well.
This 5 litre mixture is enough for 20 square metres.
Organic gardeners are permitted to use bluestone (copper sulphate), but certified growers must get permission from the organic certification authorities before using the spray.

The Organic College

The best way to avoid blight is to grow blight resistant potatoes. Here is a list you can pick from:

Best Potatoes for Foliage Blight Resistance
First Earlies
Orla
Premiere
Second Earlies
Cosmos
Nadine

Main Crop
Cara
Sante
Romano
Kondor
Sarpo Axona
Sarpo Mira
Lady Balfour
Symfonia
Verity
Pentland Dell
Pentland Squire

Best Potatoes for Tuber Blight Resistance
First Earlies
Orla
Colleen
Second Earlies
Cosmos
Nicola

Main Crop
Cara
Record
Sante
Sarpo Axona
Sarpo Mira
Kondor
Lady Balfour
Valor
Picasso

djsilver17

Thanks so much for the quick reply! I know where to get the ingredients, I know the mixture, now I just need a little guidance on spraying. For tomatoes, do I need to be careful about spraying the fruits? They've just started fruiting, some big ones already.

My garden is a mix of outdoor and a very small greenhouse. I've got 7 tomato plants in a greenhouse that is too small for them (the beasts are huge now, taller than me) and they're entirely too close together. The door is left open now so they have good air circulation and I pruned them with a vengence when I saw the blight damage starting on leaves and stems. The outdoor tomatoes are doing ok, but they're suffering from all the damp weather. Leaves not too lively, very wilty and either blight-y or some kind of mildew/fungus/I'm not sure what. But the fruits are looking good at the moment

So if you have any suggestions about spraying the tomatoes, anything I should be cautious about, or particular technique, I'd appreciate the feedback.

PS-"Dry weather"? So like... I should move my garden to Spain for a few days? :P

The Organic College

We wouldn't normally spray Tomatoes for blight. Tomatoes only really get blight towards the end of the season and it effects the fruits rather than the whole plant so it's easy to remove infected fruit. I wouldn't like to use Bluestone on tomatoes as the fruit is on the stem as opposed to potatoes with underground tubers. The easiest way to avoid blight is to ensure good ventilation in a tunnel. Keep the doors open all summer.