Fertilizing with coffee grounds: Which plants don't like this home remedy? List and tips

The gardening season is slowly getting underway and it will be a busy time in the garden for hobby gardeners. You should prepare beds, care for the lawn after winter, clean the stone slabs and of course prefer and care for plants. For many of these plants, spring is a good time to fertilize and that's exactly what today's article is about. We take a close look at a popular home remedy and explain which plants you shouldn't fertilize with coffee grounds.

Coffee grounds as fertilizer: that's what it says

In recent years it has become popular to fertilize garden and potted plants with the remains of brewed coffee. The coffee grounds used not only have a high nitrogen content, but also provide other important nutrients such as phosphorus and potassium, which many plants need to thrive. The nitrogen in coffee grounds promotes healthy leaf growth, while phosphorus and potassium support root growth and overall plant health. Furthermore, the home remedy is an ideal fertilizer for plants that love acidic, humus-rich soil.

You probably already know that coffee grounds are a good fertilizer for garden and house plants. However, it is not a universal fertilizer. Before you use it, you should find out whether it is suitable for the relevant plants.

Some plants tolerate acidic soil very well, but there are also those for which acid is as good as poison. The following plants willCoffee grounds as fertilizernot tolerated well and should not be fertilized with home remedies.

Boxwood: Since coffee is acidic, it neutralizes limescale. Boxwood hedges need calcareous soil, which is why coffee grounds are not a suitable fertilizer for them.

Lavender: To grow and bloom, lavender needs an alkaline environment. For fertilization, you can use fertilizers with potassium and should avoid those with too much nitrogen. In general, this plant does not need any fertilizer because it is a poor feeder and thrives even in nutrient-poor soil. Either way, coffee grounds are not a suitable fertilizer for lavender and, in the worst case, can lead to the death of the plant.

Also interesting:When and how should you prune a woody lavender?

Orchids: Coffee grounds are too acidic for epiphytes, allowing their roots to rot and mold to form on the surface, which can attract the attention of mosquitoes. Although coffee contains enough nitrogen that orchids need, their roots do not absorb it, leading to rot. You can find out more about the topicread here.

Rosemary: The Mediterranean herb needs fertile, loose soil with a neutral pH value. The plant does not like acidic soil and overwatering, so coffee, which creates an acidic environment, is harmful to rosemary. The plant can be fertilized twice a month with mineral and organic fertilizers that create an alkaline environment.

Tulips: These spring flowers do not tolerate acidic soil and should not be fertilized with coffee grounds. You can use wood ash as a natural fertilizer instead, especially if you have a fireplace.

Cacti: The cactus is a desert plant - it requires well-drained soil with a balanced mix of organic and inorganic substances. Coffee grounds can alter this balanced mixture, affecting the growth of the cactus plant.

This is just a portion of the plants that do not tolerate coffee grounds. However, there are also many other plants for which the home remedy is unsuitable. We have put together the most well-known of them in the list below, but they are not all of them. If in doubt, please askwhat soil your plantor plants thrive best. In principle, plants that prefer neutral to calcareous soil do not like coffee grounds.

List - you should NOT fertilize these plants with coffee grounds:

  • Luzerne
  • Crocuses
  • Tulips
  • cloves
  • Bluebell
  • Black-eyed Susan
  • American agave
  • book
  • Lavender
  • Periwinkle (Vinca)
  • Orchids
  • Pothos
  • Rosemary
  • Palmfarn
  • Yucca
  • Cacti
  • Blackberries
  • currants

Would you also like to know which plants coffee grounds are a good fertilizer for? We summarize everything important about the topicin this posttogether.

What happens if fertilization is incorrect?

Have you already given coffee grounds to a plant from the list above? Depending on what soil requirements it has, this can have a greater or lesser impact on plant health. In the worst case, the plant can die due to acidification of the soil, for example if the roots rot. This is especially true if you regularly use the coffee grounds incorrectly. However, if you accidentally fertilized a plant with a small amount of the home remedy, it will most likely not have any bad consequences as long as you don't do it again.