What would happen if you put coffee grounds on a plant? ?

Coffee is beneficial to plants especially to roses.

It won't hurt any plants, you don't put it on the plant you put it in the soil around the plants. I even use it for my house plants. And as far as I know it doesn't kill parasites but may repel them. They are very good for ferns too.

Coffee grounds are mildly acidic and provide a small amount of nitrogen. Used coffee grounds should be considered an amendment for your rose bed rather than a fertilizer; they help create a looser well drained soil. Worms also benefit from the addition of used coffee grounds which in turn creates a healthier aerated rose bed. Coffee grounds can be used in moderation on all plants, but are especially preferred by acid loving plants such as roses.

More information.

http://www.bellaonline.com/articles/art8301.asp

Used coffee grounds have many uses, from mulching to compost building. This is one ubiquitous material it's hard to have too much of. If you decide to mulch your beds and borders with ground coffee, here's a hot fashion tip: remove the filters first!

Ground coffee is high in nitrogen, making it a very good mulch for fast-growing vegetables. Many organic growers swear by coffee grounds as mulches for tomato plants, both for the nitrogen boost this heavy feeder appreciates and for coffee's ability to help suppress late blight.

You also can rid areas of slugs and snails by mixing up some instant coffee and making it two to three times stronger than you ordinarily would. Spray this concentrated coffee where slugs roam free and you'll notice a definite drop off in damage.

Good luck!

:)

I use coffee grounds in moderation but I also take the skins from a banana, cut them and bury them around the perimeter of my roses. Ialso bury them around the mperimeter of my tomato plants. They seem to thrive on the extra potassium

If you put coffee grounds around a plant you will slightly acidify the soil. It is a better idea to put coffee grounds in the compost pile, and let them incorporate into the other yard and house waste so you get a balanced compost to put around the plants.

it depends on what kind of plan