Some coffee-loving gardeners may not realize that the spent coffee grounds left behind in the pot could be used in the garden with incredible benefits.
These grounds hold some remarkable properties for use in the garden to help grow, and protect from many potential dangers and even spruce up the décor a little. Read on to learn more about coffee uses in the garden.
Adding To Compost Pile
Coffee makes for a wonderful addition to the compost bin or as a soil amendment. Sunset sent a sample of coffee grounds from Starbucks to a soil lab for analysis. The results showed coffee grinds provide generous amounts of phosphorus, potassium, magnesium, and copper. More…

Roses Love Coffee
Coffee grounds have been a “secret weapon” contributing to many beautiful roses bushes and blooms for the avid rosarian.
It serves as a good source of nitrogen, pH is neutral to acidic, lighten the soil around, attract worms that aerate and loosen the soil, and help deter some common garden pests and bacteria. More…
Coffee As Fertilizer
First and foremost, the most important property of coffee when it comes to helping the garden is the plentiful supply of nitrogen retained from coffee beans. However, it probably is not the best lawn food.
This is a must-have plant nutrient for leafy greens and vegetables. Coffee grounds can contain as much as 2% nitrogen by volume and sometimes have a carbon:nitrogen ratio of 11:1, which is ideal for any home-made fertilizer. More…
Acid Loving Plants
The high acid content of leftover coffee grounds makes them the ideal supplement for tomato plants as well as other acid-loving flowers like rhododendrons and azaleas.
No complex, secret formula here; leave the grounds to soak in a decent amount of water overnight, pour the solution into the soil or pot and that’s it! From there the nutrients and goodness of the coffee is free to do its work. Some gardeners also do this with tea but the acid content of coffee is much higher.
Change Color Of Hydrangea
This next tip may sound a bit odd compared to some of the other ideas listed (although we haven’t got on to the worms yet) but it seems that this high acidity could also be a helpful aid in changing the color of hydrangeas.
An alkaline soil tends to lead to pink blooms, which are not always as desirable as blues, so changing the soil content with some of this acidic fertilizer could potentially transform the color. More…
Mulch
Coffee grounds can be used a fine organic mulch, as long as you don’t pile it on too thick, because this can encourage the wrong kind of mold.
As a mulch, it can help control weeds, provide moisture protection and guard against heavy erosion. It is worth adding a helping hand and organic matter in your kitchen garden. More…

Boost Carrot Harvest
It seems that coffee’s reputation as a stimulant extends beyond humans! As well as giving a helping hand to certain established, acid-loving plants and fruits, coffee grounds can help carrots grow by giving them a boost of energy and stimulating plant growth.
Some gardeners mix dried coffee grounds with carrot seed for this purpose and the benefit of adding a protective pesticide for the young seedlings. More…
Pest Control
It seems that while the scent of coffee can get us humans out of bed in the morning and put a smile on our faces, it has the opposite effect on some of the creepy crawlies that we wish weren’t inhabiting our gardens.
Placing some leftover grounds around ant holes and plants that are troubled by slugs and snails can work pretty well. Slugs simply do not like crawling over the scratchy surface so a nice, well-maintained ring of grounds around vulnerable plants can be ideal. More…
Cat Repellent
Cats may not be a pest in the more common sense of the term but most gardeners would agree that neighborhood cats are not all that welcome because of the damage they can cause, the threat to local wildlife and the mess they leave behind.
Coffee grounds on the soil can deter them from digging and can also be used near potentially dangerous plants for the cat’s safety. More…
Prevent Fungal Disease
On the subject of protecting our plants, it seems that coffee can also be helpful in preventing fungal rots and wilts in some plants because the grounds create their own superior, helpful form of fungus.
The science gets a little complicated but the important thing to remember is these particular fungal growth are a gardeners friend and should be encouraged. More…
Coffee And Vermicomposting
To be honest, there is a bit of conflicting opinion on whether to sprinkle coffee to your worm bin is a good idea of not.
Some will say no, protesting that it is harmful to the creatures we want to protect; others will say yes, provided the dosage remains small enough to prevent having an acidic soil, adding that their worms show no ill effect at a little java in their soil and even seem to like it. More…

Coffee As A Wood Stain
Last, but not least, is a tip with a completely different aim that will still have a positive effect on the aesthetics of the garden.
A coffee-based wood stain on a fence or patio table won’t offer the strength and color of your standard store-bought product but it won’t have those nasty fumes and chemicals either. On a related note, it can also be used as a way to repair scratches and marks on wooden furniture. More…
These various ways to use coffee can really make a difference in your plants, compost and garden.
These simple actions and neat tricks can turn a mound of unwanted coffee waste into something incredibly useful and versatile to the point where you’ll wonder how your garden managed without it. Try asking nearby coffee shops and they will be happy to give you their spent coffee grinds.
From this one simple resource you can repel pests, fertilize plants of different kinds, treat your worms and maintain your wooden fences and furniture, proving that coffee really does have the power to rejuvenate our leafy friends as well as us.