Milk for potato blight

Heartinthedirt

So I learned today about using milk for potato (and potentially tomato) blight. Quick search on here for mentions of this returned differing opinions on semi-skimmed v. full-fat and milk to water ratios. So, anyone with 'lived experience' care to wade in - I'm all ears! 

Hostafan1

my guess, and it's only a guess, is that if it worked, we'ld all have been doing it for years. Ditto commercial growers.

Heartinthedirt

Apparently plenty of people have, Hosta, seems to have got lost along the way.

Hostafan1

@Dovefromabove's brother grows potatoes commercially. I wonder if she's heard anything.

Obelixx

The gardener featured occasionally on Rick Stein's Cornwall series swears by milk for potato blight.   @Hostafan1 lives in Devon and is only just learning to cook so may have missed that programme.

Suttons seed company recommends 1 part semi-skimmed milk to 7 parts water and sprayed on the potato foliage.  Presumably it works for tomatoes too.

Blue Onion

I did 70% water to 30% whole milk for powdery mildew preventative on my just-planted black current two years ago.  I already had some mildew on the leaves, so it was about keeping it from spreading by both gluing down any spores and also evidently when it's applied in full sun it also has some anti-fungal properties?  It didn't really harm the plant (which I was worried about, as applying liquid to leaves in full sun).. and maybe it helped?  

Not potato blight, but probably with the idea it works in the same way?  Could prevent the spread of spores between plants and maybe as a preventative.  

It appears the milk protein creates an antiseptic effect when exposed to sunlight, which is why you should apply the solution in bright sun. The protein is in the milk fat, though researchers have experimented with both whole and skim milk. Source

Heartinthedirt

Thanks Blue Onion! 

Obelixx

If you have horsetail/mares tail weed you can crush it and then soak it in a bucket of water for 2 or 3 weeks.  Make sure it has a lid as it will smell.  You need 500g of weed to 4.5litres of rain or soft tap water.  Avoid tap water with calcium content and do not use a metal container.

Strain and dilute the resulting liquid - 1 part liquid to 9 parts water - to use as an effective fungicide against peach leaf curl and a range of blights from mildew to potato and tomato blight as well as some rusts.

MrMow

Milk also works very well on Dollar spot for lawns, its the calcium that does the trick.

Heartinthedirt

Thanks MrMow. I have no idea what Dollar spot is - but I'll be on the look out now!