'Coffee grounds are an excellent houseplant fertilizer due to their high nitrogen content (about 2 per cent) that releases slowly into the potting media as they decompose.
Add used coffee grounds to your compost.
To get started, add the used coffee grounds to your compost pile, which usually consists of vegetable peels, fruit skins, and other types of natural waste. When your compost is ready, mix a small amount of it with potting soil and distribute among your plants.
Excessive acidic soil can kill or hamper the growth of plants like asparagus fern, Chinese mustard, Italian ryegrass, lavender, orchids, rosemary, tomatoes, and geranium. The roots of these plants are also not potent to absorb the nutrients added by the coffee grounds in the soil.
How Often Should You Add Coffee Grounds to Plants? You can fertilize houseplants an average of 7 to 10 days in a row, but no more, as there is a risk of over-acidification of the soil. A cup of ground coffee should be added to the compost once a week.
In most cases, the grounds are too acidic to be used directly on soil, even for acid-loving plants like blueberries, azaleas and hollies. Coffee grounds inhibit the growth of some plants, including geranium, asparagus fern, Chinese mustard and Italian ryegrass.
Don't just pour it down the drain — you can use it to fertilize your plants, both indoor and outdoor. Coffee grounds (and brewed coffee) are a source of nitrogen for plants, producing healthy green growth and strong stems. Coffee also contains calcium and magnesium — both of which are beneficial to plant health.
Not all plants are receptive to soil mixed with used coffee grounds. Take, for instance, your vegetable garden. If you grow your own food and want yours to thrive, you'll avoid adding coffee grounds by themselves directly to it.
Yes, it's possible, but it should not be more than a thin sprinkling. If you add too much, the coffee grounds will form a dense layer on the surface of the potting soil that is impenetrable to water. On a regular basis, using leftover coffee to water your potted plants is a much better idea.
Composting used coffee
Ensuring a balanced mix of 'wet' and 'dry' materials is the best way to achieve good compost. The nutrients contained in coffee grounds will be recycled back onto the soil when finished compost is used as a mulch or dug into the soil. Also add any un-drunk coffee to dry material in a compost bin.
Coffee grounds are highly acidic, they note, so they should be reserved for acid-loving plants like azaleas and blueberries. And if your soil is already high in nitrogen, the extra boost from coffee grounds could stunt the growth of fruits and flowers.
While many budding gardeners may be concerned that coffee grounds can attract pests, the reality is quite to the contrary. In fact, when implemented correctly, coffee grounds can be an effective way to repel certain pests such as wasps, snails, and mosquitoes.
Yes, succulents love coffee grounds, especially when they absorb all of the nutrients that coffee grounds provide. Coffee grounds are very acidic, and succulents grow well and love acidic soil. Coffee grounds are also loaded with nutrients including magnesium, potassium, and nitrogen.
Just like in the garden, finely crushed eggshells provide an organic source of nutrition for houseplants, patio pots and hanging planters. Sprinkle the pulverized shells on the soil surface and they will break down over time whether you are using eggshells for houseplants or outdoor containers.
Keep It Shelved
The best way to keep ground coffee or whole beans fresh is to store the coffee on a pantry shelf in an opaque, airtight container.
While coffee grounds are a fantastic addition to your compost, the nature of their decomposition is not effective for most orchids. In addition, they cause rapid decomposition of orchid potting bark, creating an environment that is primed for root rot. It is best to save those grounds for other plants.
The key is to only use coffee as a substitute for water once a week. Because just like too much coffee is a bad thing for humans (beware the jittery, anxious, over-caffeinated mess I become if I drink more than six cups), it's also a bad things for plants.
Coffee grounds can be used when planting perennials, shrubs and bushes, or added to the soil around those growing throughout the year. Adding a few tablespoons when planting perennials helps add nutrients and soil structure for long-term growth.
Since coffee grounds have such a pungent and intense smell, mosquitoes do not like to come near it. Mosquitoes are repulsed by all types of coffee, whether it is fresh, used, or burnt. The most effective way to use coffee grounds for mosquito control is by burning them, as it creates a stronger aroma.
Like any type of fertilizer, coffee grounds are only effective when used sparingly. It is never a good idea to add too much, as that could do more harm than good. The proper proportion is usually around 4 to 1, or twenty-five percent of coffee grounds to mineral soils by volume.
She recommends that grounds make up no more than 15 to 20% of the total compost volume. Because they are acidic, coffee grounds make good acid mulch. Of course, too much of anything is just too much, so apply coffee grounds in limited amounts. Kit recommends a layer no thicker than half an inch.
Eggshell Benefits
As it happens, eggshells can provide all the calcium carbonate the soil needs, which helps to lower the soil's pH level and make it more alkaline as opposed to acidic. This is incredibly beneficial for plant growth because many plants prefer to grow in soil that has low acidity.
Eggplant, peppers, broccoli, cauliflower and leafy greens, to name a few. But don't go overboard. Since it takes a while for the shells to decompose, Uyterhoeven recommends applying eggshell fertilizer to your garden or indoor plants just twice a year—in the fall and spring.
One final note: Make sure your soils aren't already alkaline before you add anything to up the pH; and never ever use eggshells or other pH-raisers around acid-loving plants like azaleas and rhododendrons.
The green fungus called Trichoderma, is very beneficial to the soil. The blue-green fungus is moderately beneficial. At any rate, moldy coffee is good to use directly in the garden, on your houseplants, or in the compost pile.