Spraying your plants with a fertlizer is sometimes the best way to feed a plant or to force it to go that extra mile.
In AP I like to spray the fish water over the plants and they respond well. The micro activity on the plant keeps a lot of bugs away and the leaves are able to take in extra nutrients that can be locked out in the root system. You can use a lot of different stuff for a foliar feed, seaweed(seasol) is a popular choice. What my sibling did was not quiet what I would recommend.
He mixed up a brew of a couple of handfulls of dynamic lifter in 1 ltr of water and went to spray the expensive roses in mums yard. The plants turned black and the leaves fell off. I recommended a hard prune with a brush cutter and hose the plants off.
In most cases I like to add dynamic lifter to the base of the plants and let it work its way into the soil. A foliar Fertilizer is a very diluted mix because the plants leaves are able to take in quiet a lot and its easy to overload or just plain burn the plant.
Backyard Farming Forum
Then mites attacked the plants. He says the problem was the mites...I say the problem was the spray was too strong which weakened the plants and allowed the mites to take over. I banned him from foliar spraying for a while and have insisted he measure the amount he mixes next time. The tomatoes are now reshooting healthy new growth
