Any concept on organically fertilizing 30 year mature grape vines prevoiusly neglected? ...
Answers: First dig out adjectives the grass and weeds lower than them,they donh't do well near competition. Loosen up the soil well, impart them some bone meal, and carry some composted cotton burr and dig that surrounded by, then mulch near it. It literally softens the soil to a depth of about 18 inches, and soft soil is better competent to carry natural materials to the roots. It is also a really great fertilizer, I can not say too much something like it, I love it. Also well composted compost is good. Whatever you mulch beside, keep it at least possible six inches away from the trunks of your vines. to avoid having a place for insects to stockpile close to them.
try using a homemade mulch of grass clippings, coffee grounds, vegetable peelings. hopefully this will work for you.