Because I have a lot of phomopsis in my vineyard I’ve read the best thing to do is spray the vines with lime sulfur after winter pruning close to bud swell. I made a couple gallons for next year, buying it was too expensive. About 4 lbs sulfur to about 2 lbs hydrated lime in about 3 gallons of water, stir and boil for about an hour. It makes a mess if you put a lid on the pot and let it boil over. Other wise very easy to make. Hope this helps someone else. BTW a 50 lb bag of hydrated lime cost $8. I’ve got 48 lbs left over