The issue with coffee grounds is that they are fine particulate that compacts
and clogs up the drainage in the potting mix. Secondly, they are often high in salts,
which can accumulate in your soil and lead to potential problems. High salts are a
major cause of browned leaves and leaf-tips. Thirdly, coffee offers a very minute
and unpredictable amount of nutrients, so you don't really know what you're providing.

Coffee grounds are wonderful in raised beds, gardens, and as mulch around the yard.
But for my special container plants, I go to great lengths to keep my mixes free-draining
and flushed of excess salts.

Josh

While the use of coffee has some benefits for growing plants, may I say again that soluble fertilizers are made for plants and not for us to consume. Best to stick with what is intended for its purpose.

Coffee grounds are excellent for the compost, work bin and bokashi. i would not fill my hoya pots with this stuff as they do leach out other significant microorganisms that assist in nutrient absorption.