Coffee grounds are a popular and inexpensive natural fertilizer. After brewing the coffee, you can save the leftovers, dry them, and mix them with topsoil.

It is a very suitable fertilizer for plants such as rose bushes, blueberries, strawberries, rhododendrons, azaleas, and hydrangeas.

However, not all plants tolerate this type of fertilizer well. In this article, you will discover which plants are best not to fertilize with coffee grounds.

Why shouldn’t you fertilize some plants with coffee grounds?

More and more hobby gardeners are looking for ecological alternatives to care for their plants. Some turn to natural fertilizers made with simple ingredients such as coffee grounds, milk or even rice water. However, not all plants benefit from coffee grounds.

Coffee is a suitable fertilizer for plants that prefer slightly acidic soils:

• Vegetables: like green beans and tomatoes.
• Ornamental plants: rhododendrons and hydrangeas.

On the contrary, it is not recommended to fertilize those plants that prefer alkaline soils with coffee grounds.

Plants that you should not fertilize with coffee grounds

Some plants are sensitive to the acid in coffee grounds and need more alkaline soil. These are the plants that you should not fertilize with this fertilizer:

1. Gladiolus

Gladioli require alkaline soil with a pH of at least 7.0. Instead of coffee grounds, it is advisable to use compost and horn shavings to enrich the soil of these bulbs.

2. Chrysanthemums

Chrysanthemums, colorful late summer and fall plants, also prefer alkaline soil. They do not require constant fertilizing, but if you decide to fertilize them, opt for a high-quality liquid flower fertilizer. It is important to keep the root ball moist and not let it dry out completely.

3. Asters

Asters need more alkaline soil. The best option to fertilize them is compost, since coffee grounds can negatively affect their development.

4. Forsythia

This beautiful yellow-flowered plant has difficulty in acidic soil, so coffee grounds are not suitable. Forsythia thrives best when left alone, without needing to be treated with a fertilizer.

5. Berry bushes

Berry bushes, such as currants or gooseberries, do not tolerate acidic soils well. For them, it is better to opt for a specific organic fertilizer for berries.

What should be taken into account when choosing fertilizers for your plants?

Not all plants have the same needs, so it is essential to know the particularities of each one before applying any fertilizer.

There is 17 essential nutrients that all plants need, including carbon, hydrogen and oxygen, which plants obtain from air and water. Nitrogen, phosphorus and potassium are needed in greater quantities than other nutrients; They are considered primary macronutrients.

Keep in mind that over-fertilizing is not only a waste of money, it can harm plants and the environment.

There are many options. For a good choice, it is advisable to know the characteristics of the soil and the needs of each plant. In general, organic fertilizers are recommended, such as compost that is used in certified organic production and that feed the soil microorganisms, therefore improving their general health.

Additionally, you can use grass clippings or cover crops to enrich the soil.

If you don’t have plants that benefit from coffee grounds, don’t throw them away! The grounds are excellent for removing odors from your hands, such as the smell of onions. Simply rub your hands with them and you will notice how odors are neutralized. This is just one of the many uses for coffee grounds.