You might want to rethink using coffee grounds. I know people use them in gardening but they are not the best thing to be putting in your soil. They are highly acidic, still contain caffeine, and they have antibacterial properties that are good if you're drinking a cup of coffee but not so good for the microbes in the soil.
This popular soil additive may not be the best thing for your plants.
www.discovery.com
"Caffeine is a purine alkaloid synthesized by several eudicot plants, including coffee, cacao (
Theobroma cacao), and tea (
Camellia sinensis) (Fig. 2). Caffeine is synthesized in both coffee leaves, where it has insecticidal properties (
15), and fruits and seeds, where it inhibits seed germination of competing species"
science.sciencemag.org
There are frequent anecdotal recommendations for the use of locally produced spent coffee grounds in urban agriculture and gardens, either through dir…
www.sciencedirect.com