He would be better of using a dry sprinkle-on fert with trace elements
rather than the liquid for this season. A light dusting of powdered milk
[cheap generic] and epsom salts [a light-med sprinkling] about every 4-6
inches of water.

If he has pets, water in the milk before they get to it. I rush out
just before a rain. [Usable if expired]

And any sugar can be added- I like maple syrup from the $ store. About
1/2 C [mixed in any amt of water over 100 sq ft, also every 5-6 weeks
will help too. [regular granular is ok but doesnt help flavor as well
[about 1/2C over 100 sq ft] No, no ants.

He should also chew up is leaves in fall and mix them in the soil