Even if the azalea does not have many requirements, it is happy to be fertilized every now and then. We show what you have to consider when fertilizing azaleas.
Basically, the name "Azalea" is a pretty vague term. The beautifully flowering plants are actually members of the Rhododendron genus (Rhododendron). Which rhododendron species is considered an azalea and which is not depends on the leaves: deciduous and small-leaved rhododendron species are called azaleas. This also includes the native alpine rose (Rhododendron hirsutum). Some azalea species can therefore be kept outdoors, while the two species potted azalea (Rhododendron simsii) and Japanese azalea (Rhododendron japonicum) are indoor azaleas enjoy particular popularity. In order to keep your Azalea - of whatever type - in good he alth, it is important that you take a closer look at how you fertilize it.
Azaleas thrive in many parts of the world - and even in Germany. What unites them all is their love for hummus. The plants are pronounced shallow roots. They spread their root system just below the surface, where the humus content is highest. In contrast to the subsoil, a rather acidic environment often prevails here, as the azaleas like it. So, when fertilizing azaleas, you should not only consider the nutrients, but also the soil pH and humus content.
The right time to fertilize azaleas
From mid-April it's time to open the fertilizer season. Since slow-release fertilizers work best for azaleas, they are also fertilized at this time. The nutrients are then released continuously until autumn. However, fertilizers with a long-term effect of less than four months should be applied a second time after flowering. However, you should not apply any fertilizer during flowering and shortly after.
The perfect fertilizer for azaleas
For azaleas in pots, slow-release fertilizers of various forms are the best choice. There are various rhododendron fertilizers that are suitable for azaleas. Actually, however, it mainly depends on the nutrient concentration. This should be such that nitrogen and potassium are represented in roughly equal proportions. Phosphorus, on the other hand, should be slightly less. Our Plantura room and green plant fertilizer is also ideal for azaleas and can be easily applied to the pot with the irrigation water. It consists almost exclusively of organic material and thus contributes to an active build-up of humus. In general, you should prefer fertilizers with organic components for azaleas and other types of rhododendrons, as humus is extremely important for these plants. If you have chosen a fertilizer that is not physiologically acidic, then you should not forget to check whether the soil still has the right pH value. If he gets too angry, you should take countermeasures.
Planted azaleas that are not deprived of nutrients usually do not need any fertilizer at all. Simply put the faded blossoms back at the feet of the azalea. In this way, the flowers of the plant are converted into humus and the nutrients contained can be absorbed by the plant again. This can create a nutrient cycle.
Fertilizing azaleas organically: Instructions for application
Our Plantura indoor and green plant fertilizer is ideal for the organic fertilization of azaleas. Shake the bottle before use and add 15 milliliters of fertilizer to 5 liters of irrigation water… The sensitive roots of the plant are just below the surface of the earth, in the top layer of soil. The advantage of liquid fertilizer is that the roots are not damaged or stressed and the plant still has valuable nutrients.
If azaleas are allowed to keep their own dead leaves and flowers as a mulch around their roots, they only need to be fertilized on rare occasions.
Since the acidity quickly falls short with organic fertilization, it is advisable to acidify the soil if necessary. This is easier than it sounds and you can safely do without peat. Simply add a layer of pine litter or leaves, preferably oak leaves, to the soil above the root space. If this is not an option for aesthetic reasons, you can also compost the leaves beforehand and distribute the leaf compost. Is simple and effectivealso a layer of bark mulch. Just like leaf and needle litter, this also protects the soil from drying out and promotes soil life and humus build-up.
Fertilize azaleas with blue grain and co
Azaleas can be fertilized with mineral fertilizers, but this is not ideal. Regardless of the problematic environmental aspects, they cannot contribute to soil fertility and humus formation. And humus is the favorite abode of azalea roots.
If you still want to use mineral fertilizers, then it is best to use rhododendron fertilizers. These have the right nutrient ratio and are also physiologically acidic, which is vital for azaleas, especially in alkaline soils. In addition, fertilizers with a depot effect are advantageous because the plant is continuously supplied with nutrients. This is better for the plant and at the same time protects the gardener.
You can also use blue grain, but be careful here. The nutrients in blue grain are highly dosed, which in the worst case can lead to over-fertilization. The leaching of nutrients and the resulting threat to groundwater are arguments that must be taken seriously. Therefore, use highly concentrated fertilizers such as blue grain only sparingly. To maintain a long-term supply of nutrients, you must use blueseed regularly.
Fertilize azaleas with home remedies
The most prominent example of the use of home remedies is certainly coffee grounds, which are ideal for azaleas due to their nutrient composition and slightly acidic effect.
If your tap water is soft and has only a small amount of lime, then you can balance the cooking of potatoes with the watering of your azaleas from time to time. The cooking water is enriched with valuable nutrients and, when cooled, contributes to the he alth of your azalea.
Fertilize azaleas - in short:
- Fertilize from spring to autumn, not during flowering and shortly after
- Slow-release fertilizer makes sense
- Nutritional content: nitrogen and potassium roughly balanced, less phosphorus
- Prefer organic fertilizers as they promote humus build-up. Humus is very important for azaleas
- Check the pH of the soil and, if necessary, acidify it with various organic substances