Fertilize cacti: when, how and with what?

Cacti usually accompany their owners for many years. Here you can find out what you should consider when fertilizing a cactus.

If you don't have a green thumb, you will at least get a cactus (Cactaceae) to make ends meet – at least that's what they say. In practice, however, one hears the phrase "Even the cacti are dying for me" again and again. Fortunately, caring for these undemanding creatures is not that difficult. And with a little knowledge you can already achieve a lot.

Cacti grow slowly. No wonder, because the resistant plants come from the sparse regions of America. To better understand cacti and their claims, you should take a look at the world of prickly Contemporaries dare: It is mostly dry here and the rare availability of water determines the rhythm of the life. The vegetation all around is sparse and so there are few dead plant parts that could be converted into humus. The earth therefore consists mainly of mineral components. To make ends meet, the cactus must build up biomass slowly and steadily.

With these conditions in mind, you basically have all the knowledge you need to keep your cactus happy.

When should you fertilize cacti?

It rarely rains in her home country, but it does rain heavily. Only then can the cacti absorb nutrients from the water. The fertilization is therefore strongly dependent on the watering and should also be done via the irrigation water. Our Plantura Organic room and green plant fertilizer is ideal for this because the liquid fertilizer can simply be added to the irrigation water. During the growing season, you should fertilize every one to four weeks, depending on the cactus species.

In winter, cacti, like most plants, need a rest period. Therefore, the last time of the year is fertilized in August. The first dose is only given in April or May, after the cactus has started the growth season. The main fertilizing time is in June and July. In these two months you should give your cacti more fertilizer than in May and August.

Recognizing deficiency symptoms in cacti

Cacti generally get along with few nutrients. As a rule, it is therefore better to fertilize too little than too much. Too much can quickly lead to soft tissue and horny drives.

Deficiency symptoms, however, only appear late and do not grow together so quickly. Therefore, try to find the right amount of fertilizer. If the cactus begins to lighten, then this is a clear sign of a lack of potassium or nitrogen. The lightening is usually strongest at the base of the cactus and will sooner or later become lignified. The deficiency is also accompanied by a slowdown in growth.

The cactus can also lack phosphorus. However, this deficit manifests itself more subtly in the absence of flowering, because phosphorus is particularly important for the development of flowers and fruits.

The perfect cactus fertilizer

Over 100 species of cacti are known worldwide. So it is logical that not all cacti have the same requirements. The family is diverse. However, there are fundamental similarities in terms of nutritional requirements.

Nitrogen is absolutely vital for cacti. It promotes growth, but in excessive amounts also leads to soft tissue and a higher susceptibility to disease. So the perfect fertilizer contains nitrogen, but in moderation.

Potassium is essential for stability, so it is also of great importance for cacti. It also plays an important role in storing water in the cells. A good fertilizer should therefore contain sufficient potassium, ideally even more than nitrogen. Phosphorus is also more important than nitrogen when it comes to fertilization. This nutrient is particularly important for the formation of flowers and fruits.

In addition to various essential trace nutrients, the perfect cactus fertilizer contains nitrogen, phosphorus and potassium. The main difference to conventional fertilizers, however, lies in the ratio. While fertilizer usually contains significantly more nitrogen than phosphorus and potassium, this should be the opposite with cactus fertilizer. If there is as much or even less nitrogen than phosphorus or potassium in the fertilizer, it is suitable as a cactus fertilizer.

Last but not least, you should of course not ignore the pH value. Cacti need a pH between 6 and 7. Only then do they feel really good and can thrive. On the other hand, if the value is too acidic or too basic, some nutrients become less available to the plant.

Fertilizing cacti organically: The right approach

If you like to fertilize your plant organically, you will be disappointed with cacti. In the region of origin of the robust plants only little thrives and so there are also few plant parts from which humus could be formed. In addition, animals hardly find anything to eat here, which is why there is little dung. Cacti therefore mainly draw their nutrients from the mineral components of the soil. For primarily organic fertilization, a liquid fertilizer such as ours is recommended Plantura organic indoor and green plant fertilizer. Mixed into the irrigation water, the valuable nutrients can be easily added to the previously moistened cactus substrate. An advantage of cacti is that with infrequent watering there is no risk of leaching.

Fertilize cacti with minerals

Any fertilizer with the right nutrient ratio is suitable as a mineral fertilizer. Cactus fertilizer naturally meets this requirement, but is often more expensive than other fertilizers. Mineral salts can also be dissolved in the irrigation water and used as fertilizer. However, moisten the substrate before using fertilizer-enriched irrigation water.

Fertilize cacti with home remedies

In fact, there is an organic home remedy that is great for cacti: coffee grounds. This is generally not very nutrient-rich, which makes over-fertilization difficult. In addition, it contains mainly phosphorus and potassium and only in third place nitrogen, which perfectly meets the needs of cacti. As a bonus, coffee grounds are acidic, counteracting too high a pH. Especially with calcareous irrigation water, this home remedy can bring the rescue.

Make cactus fertilizer yourself

Since cacti are more used to a mineral environment, making the fertilizer yourself is not that easy. To do this, you would need to acquire the individual nutrients - i.e. nitrogen, phosphorus and potassium - as well as the micronutrients such as copper and zinc and mix them together in the right proportions. Apart from the fact that mixing them together requires special conditions, you unfortunately cannot save any money in this way, because the individual nutrients are expensive in normal household quantities.

Even though cacti are generally the easiest creatures to care for, there are still a few things to consider. You can find out how to properly care for your cacti in our article on Caring for cacti and soukkulents.