What Plants Do Coffee Grounds Help? (Find Out)

Why waste the coffee grounds when you can use them for some gardening work? 

Coffee grounds contain nitrogen which is essential for all plants to grow but using coffee ground directly won’t do the job as some plant favors ratio of carbon to nitrogen. So, the right thing to do is to add coffee ground in your worm bin or compost.

You need to understand that some acidic-loving plants will grow well with the help of coffee grounds. Still, others can’t stand coffee beans, and coffee grounds might inhibit the growth of the seed and kill good bacteria because of their antioxidant property

Some of the plants that coffee grounds help are: 

  • Blueberries
  • Carrots
  • Roses
  • Radishes
  • Azaleas
  • Cabbage
  • Hollies 
  • Lilies
  • Rhododendrons 
  • Radishes 

Where these plants can thrive in acidic soil, some plants like tomatoes or lavender won’t because the caffeine in coffee grounds can be toxic for their growth. 

Let’s look into what plants do coffee grounds help and the benefit of using coffee grounds in your garden. 

Can You Use Coffee Grounds For Your Garden?

coffee beans on hands

You can use coffee grounds in your garden as they are rich in nutrients that can boost the growth of your plants. 

Many gardeners swear of its excellent benefits for a healthy, happy garden, but this will only work on certain plants-not all. 

The right way is to use them in your compost instead of adding them directly to your garden.

Out of two types of composite materials, brown and green, grounds might look brown, but they contain about 1.45 % nitrogen in compost. 

You need to balance it with brown material such as dry leaves. The key is to balance 4-1 of brown and greens materials, respectively. Less amount can hinder the heat process, while too much f green can make compost smell. 

Coffee grounds have many useful components. See the table below:

Components Amount (g/kg)
Potassium11.7
Magnesium 1.9
Phosphorus 1.8

How Does Coffee Grounds Help Your Garden?

black soil on a wooden spoon

There are several ways in which coffee ground can be a helpful hand for your garden. 

Coffee grounds help retain water and are also a natural fertilizer for your garden as it has nitrogen that aid plants to grow. 

It also helps you with vermicomposting as they attract worms. On the other side, it can also be used as an anti-pest because coffee grounds are abrasive that prevent the pests like snails and slugs from crawling over your plants.

The coffee grounds are water-soluble, which means they are not much acidic and can ruin plants’ pH levels. You can find most of the coffee grounds have 6.5 to 6.8 pH levels.

Nitrogen, potassium, calcium, magnesium, chromium, and iron are some essential minerals found in coffee grounds. These nutrients act as fertilizers and help plants nourish well and absorb nutrients from coffee grounds without depleting the soil.

You can also put coffee grounds to work as mulch that helps decrease weed growth and keep the soil moisturized

Coffee grounds can also be used as compost, which impacts the nutrient level of plants and reduces gas emissions.

So, if you have a garden, then using coffee grounds to charge your garden is more reasoning than throwing the coffee grounds in waste. 

What Plants Don’t Like Coffee Grounds?

Tomatoes, Black-eyed Susan, Orchids, Pothos, Rosemary, Sago palm, Yucca, and Lavender, are just some of the plants that don’t like coffee grounds.

Now the thing is, some plants like chocolate and coffee plants produce caffeine independently, and this is what biologists call “convergent evolution.”

When some plant species produce something on their own, they compete and kill that thing in their surrounding plant. Sound intriguing to you, but this is how plants work. 

Before you think that coffee grounds don’t have any caffeine, the Journal of Agriculture and Food chemistry study says otherwise. 

According to a study, a coffee ground can have as much caffeine as a cup of coffee depending on how you brew and steep it. It can range from 8 to 10mg caffeine per gram of coffee ground.

Some of the plants that don’t grow well with coffee grounds and might get ruined if you use them are: 

  1. Lavender

 Lavender likes hot and dry sandy soil. They can’t stand acidic soils so, coffee grounds are not for lavenders.

  1. Orchids 

Coffee grounds are too acidic for epiphytic orchids and can root the rot by clogging it up. Plus, orchids don’t like to grow in organism soils not they break down nitrogen in coffee. It’s a no for orchids.

  1. Pothos 

Pothos are houseplants and don’t need extra care to grow. Adding coffee ground can ruin the pH level of soil, which is not suitable for Pothos growth.

  1. Rosemary

Rosemary likes acidic soil, but still, professional gardeners don’t recommend using the coffee ground for rosemary until you dilute it with enough water to suit the soil’s pH level.

Benefits of Putting Coffee Grounds in Your Garden

We have mentioned the variety of ways you can use coffee grounds in your garden and the right way to use them. Now let’s have a look at some of their benefits that might intrigue you to use coffee grounds from your next brewed cup of coffee in your garden. 

Soil Water Retention

Coffee grounds can retain water, which helps plants to thrive in moist soil. Using coffee ground can make the plant’s soil remain moist for a more extended period after watering. Also, coffee grounds retain water for more extended means you need to water your plant less. 

Improve Soil Drainage

Adding coffee ground into the soil can improve the quality of soils. The coffee ground contains organic material that will enhance the drainage by ensuring water doesn’t stick in the roots, leading to rotting

Aid to Aerate the soil 

When coffee grounds are added to the soil, they amend the soil with much organic material, improving the aeration and overall plant health.

Deter the Snails and Slugs

Gardeners use it as a deterrent to prevent snails and slugs. These nasty pests feed on foliage that can become nausea for gardeners by deteriorating the plants. 

Act as Cat Repellant 

Cat use soil, gravel, and mulch as their litter trays, and this can be frustrating sight plus dangerous if you step on their poop or pee. If you have a cat, you might have noticed they don’t like the coffee ground smell. 

Using coffee ground with other preventative method help this little creature stays from your garden. 

Can You Put Coffee Grounds in Potted Plants?

a potted plants next to a small shovel with soil

You can put coffee grounds in your potted plants. 

Coffee grounds work as fertilizer for the garden as well as for houseplants. The nitrogen helps your potted plants stem from growing strangers and greener. 

The most recommended way by professional gardeners is using coffee grounds in the compost pile. You can mix the compost pile with your potted plant but make sure to dilute well. Like you dilute your fertilizer, adding a gallon of water to a spoonful of coffee ground will work as a natural fertilizer for your potted plants. 

Diluting or adding coffee grounds to compost is necessary because adding them directly to potted plants can retain the moisture and cause fungal, inhibiting plant growth. 

Instead of purchasing expensive fertilizer from the market, switch to the cost-effective way by using coffee grounds in your potted plants and garden.

How to Use Coffee Grounds as Fertilizer?

Coffee grounds are a cost-effective and handly available natural fertilizer for your garden. 

Sprinkle it on top of your plants or scratch it in soils. It will recharge your garden with nutrients and nitrogen. Most people worry about the acidic effect of coffee grounds, but they are neutral in pH means not as much acidic as it might appear. 

Instead of adding it directly, make a liquid fertilizer out of the coffee ground and use it as a concoction on plants. To make a tea out of the coffee ground, take 3-5 gallons of water, add 2-3 cups of used coffee, and then steep it for 2-3 hours. 

Final Say

Coffee grounds prove to have a positive impact on gardens. However, there are some plants that don’t grow well with coffee grounds. 

Nevertheless, coffee grounds could play many different roles in your garden. From fertilizer to improving weed growth and using mulch. These many benefits should be enough to make you try to use coffee grounds for your acidic-loving plants. 

You can also use them on potted plants. Although, you have to be very careful.

Watch the video below to learn more:

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Matt Marshall

As I learn more and more about coffee and coffee products I want to share all my learnings with you here on this website. I hope you find my articles useful and entertaining to read.

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