Jim Carter said:

A friend's garden is not doing well. He has not mixed manure or other organic
material with the soil since he started gardening three years ago. Plants in
his garden are just not growing. The problem is that he has been relying on
short-cuts such as Miracle Grow.

Is there any product he can add now that would let him salvage this year's crop
without digging up the garden and adding manure?

Alfalfa meal or pellets, lightly scratched in or as a thin mulch. Screened compost
or *very* well aged manure, as a heavier mulch. Both in combination, even
better.

Alfalfa tea or liquified kelp (Maxicrop powder is what I use) as a foliar feed.
--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)