Zinc seems to be the trace mineral that lacks the most. To replenish it, some suggest 2 bushels per acre, some 2 pounds per tree per year, one thing is clear, if you apply too much, the tree or bush will take only what it needs and will not be damaged in any way. Any excess will leach into the soil eventually.

When do you need to use zinc? The symptoms of lack of zinc are very clear.

Yellow streaks between the veins on the leaves.
Overall yellowing of the leaves, which should be deep green
Stunting of the tree
Shortening between the nodes on the branches.
Slow growth.

How much to use? I just started using it myself and my first experiment includes 4 trays of privets.

I will use only water in the first one which is my control tray.
Spraying the foliage on the second one (suggested method),
bottom feeding on third one
spraying and bottom feeding on the last one.

I used a 1 gallon sprayer with 2 ounces of Zinc which disolved immediately and did not give me any problems going thru the nozzle.

For larger trees you can just sprinkle the zinc around the drip line and then water it do make it go into the soil. May be you can find the exact amount to give without wasting too much product.

If you come up with some information I can use to give my readers better understanding on this matter, please send it to me. I will add it to this page.

One last word... be careful, do not sniff the stuff, all these chemicals are harmful to the body in some way.

If you can't find zinc at your favorite nursery, I have some, it is at the fartilizer page.