Fertilize oleanders: timing & procedure

A balanced nutrient ratio is required for a magnificent oleander blossom. You can find out when, how and with what to fertilize oleanders here.

Even though Vincent van Gogh is best known for his love of painted sunflowers, the oleander (Nerium oleander), also called rose laurel, a place in the colorful world of the artist. No wonder, because the delicately feminine flowers still enchant hobby botanists and friends of beautiful things to this day. In order for these striking flowers to appear in harmonious white, yellow to pink-red tones throughout the summer, the plants need more than just warmth and sun. A sufficient supply of nutrients in the form of regular fertilizer application should also be ensured for these heavy feeders, especially in tub culture. At the same time, you should pay attention to the special needs of the oleander in terms of soil conditions.

Oleanders spread a Mediterranean ambience within the native flora in the tub on the terrace and the balcony, sometimes also planted out in the bed. But in order for the flowers to last from mid-June to September, the plants need a lot of nutrients. So that you know how to use the right fertilization to increase the number and size of flowers in your oleander in can drive up, we explain when, with what and how often you fertilize your plants should.

Fertilize oleanders: the right time

As with every plant, the right time plays an essential role for successful fertilization of the oleander.

Fertilize oleanders when planting

Already when planting or repotting your oleander, you can bed your green darling in plenty of nutrients. For this, the earth is used mature compost or another organic long-term fertilizer mixed in. An additional enrichment with rock dust also provides your oleander with all the important trace elements and a load of lime, which ensures the right soil pH value between 5.8 and 7.0. After repotting or planting, you should only use fertilizer again after six weeks at the earliest.

Fertilize oleanders in spring and summer

Otherwise, the oleander is fertilized for the first time after leaving its winter quarters in the spring. This start fertilization takes place as soon as the outside temperature is around 15 °C. Now the growing season of your Mediterranean plant begins. This is usually around April or May. The plant itself also signals when it needs nutrients again. If the leaves of your oleander slowly turn darker again after the hibernation, the time has come for the first fertilization. Fertilize your oleander about once a week to every 14 days from spring to the end of August. If a long-term fertilizer is used, the initial fertilization in spring is sufficient, as is further fertilization in early summer. This choice not only saves you one or the other application of fertilizer. Use a slow release organic fertilizer like ours Plantura organic flower fertilizer, also protect your oleander from over-fertilization. In addition, they not only promote the health of your plant, but that of all soil life.

Fertilize oleanders in the fall

The fertilization of the oleander is stopped from autumn so that the newly formed shoots have enough time to mature until winter. To support this maturing process, autumn fertilization with potash fertilizer can be carried out in August. The potassium supports the rapid maturation of the shoots and makes your plant more resistant to low temperatures. It should be borne in mind that even with this support, the Mediterranean shrub should not be exposed to temperatures below -5 °C. In winter, the fertilization is then completely stopped, the plants need their hibernation. In this they run on the back burner and do not need any additional nutrient supply.

Summary: The right time to fertilize oleanders

• When planting or repotting, mature compost, rock dust or another long-term fertilizer is mixed into the soil; after that, do not fertilize for at least 6 weeks
• Fertilize regularly every 1-2 weeks from spring (March/April) to the end of August; when using an organic slow-release fertilizer like ours Plantura organic flower fertilizer A single fertilization in spring and another in early summer is sufficient
• Autumn fertilization in August with potash fertilizer for greater resistance in winter

Fertilize oleanders: deficiency symptoms

If the otherwise always green leaves of your oleander turn yellow and fall off, this can be due to deficiency symptoms such as a lack of water or nutrients. However, it can also be part of the normal life cycle of the oleander, as the leaves are only two years old and then say goodbye. Before that, all the nutrients contained in the leaf are released to the plant. As a result, the yellow discoloration occurs before the leaves are shed. You should therefore only worry about your oleander if many leaves are shed over a short period of time. The way the leaves change color before they are dropped can also make it easier to find the reason. Pale leaves with visible veins and no or poor flowering indicate a nutrient deficiency.

Emergency fertilization with mineral fertilizer helps here. This is available more quickly than the organic variant, which is an advantage when combating a deficiency symptom quickly. However, make sure that the administration of highly concentrated mineral fertilizers does not turn the deficiency into over-fertilization. Often an undersupply of nutrients is not due to too little fertilizer, but to a wrong one Soil pH by using very soft irrigation water or acidifying nutrient sources such as ammonium fertilizers or Coffee grounds as fertilizer. These lower the pH value in the soil and thus limit the availability of nutrients. This can be remedied by repotting, watering with hard tap water or lime fertilization with rock flour or eggshells.

Fertilizer for oleanders: how and with what to fertilize?

Specialist shops offer special fertilizers for oleanders or Mediterranean plants. In addition to the important primary nutrients nitrogen, potassium and phosphate, these also contain trace elements such as magnesium, boron, copper, iron, manganese, molybdenum and zinc. Especially in pot culture, these minerals are quickly depleted due to the low soil storage capacity and the oleander's highly consuming nature. However, any other flower fertilizer can also be used. If important trace elements and minerals are missing in the fertilizer, you can also give rock flour. Also make sure that you avoid very nitrogenous fertilizers so that your oleander puts its energy into abundant flowering and not into strong height growth.

Our Plantura organic flower fertilizer With an NPK ratio (i.e. nitrogen to phosphate to potassium) of 4 – 2 – 7, it is an ideal source to cover the nutrient requirements of your oleander. The extra potassium also supports the frost resistance of the plant in winter, because it accelerates the lignification of the shoots. Due to the complex form in which the organic components are almost exclusively present, the nutrients are slowly released into the soil. So you only have to use fertilizer once a year and avoid harmful over-fertilization. If you want to maximize the number and size of flowers and promote reblooming, it is best to fertilize with a phosphorus fertilizer. This is given at most every four weeks.

Long-term organic fertilization for oleanders: instructions and dosage amounts

Our Plantura organic flower fertilizerr with organic long-term effect offers you a long-lasting and environmentally friendly supply of all important nutrients, because too excluding animal products and using almost exclusively organic sources is an all-round care for your oleander possible. To ensure that fertilization is successful, we explain step by step how to use our correctly Plantura organic flower fertilizer.

1. Before planting 100 - 150 g/m² (well filled 0.2 liter glass) of ours Plantura BiO-flower fertilizer work into the top layer of soil
2. Pour the soil and freshly added oleander well so that the granules can dissolve well
3. For maintenance fertilization in spring, you should fertilize another 80 - 120 g/m² (0.2 liter jar) per plant

Especially with the tub culture, it is important not only to think of the usual macronutrients such as nitrogen, phosphate and potassium. Since oleander is one of the heavy consumers, trace elements such as iron, magnesium and calcium should also be applied. Because in the limited conditions of a bucket, the supplies stored in the earth are quickly used up. This can be remedied by rock flour, which is spread on the ground in the root area once a year in spring. Then it is poured vigorously. Apply 150 to 300 g per m² depending on the lime content of the soil. The more calcareous the soil, the less you should fertilize. At the same time, the rock flour has the advantage that the soil pH value is buffered for the Mediterranean plants. The plants feel particularly comfortable at a pH between 5.8 and 7.0. The plants here do not have very high requirements.

Fertilize oleanders with minerals: blue grain and co.

Especially with plants like the oleander, which are usually kept in tub culture, you can also use the mineral fertilizer variant. However, make sure that you fertilize blue grain and Co. according to the manufacturer's instructions and also supply the necessary trace elements. Because even if over-fertilization is not life-threatening for the oleander, it is not good for the health and appearance of the plant. Over-fertilization is indicated by a brown discoloration of the leaf edges.

The damage to the fine roots of the plant caused by the salinity of the soil remains invisible. If you over-fertilize the tub with your oleander, rinse it with plenty of water without waterlogging and only fertilize again when the plant has recovered. This can sometimes take a long time, because the damaged leaves have to be shed and replaced with fresh leaves.

Fertilize oleanders with home remedies: coffee grounds and co.

Even what is usually declared as waste can still serve as a source of nutrients for the oleander. Better to let coffee grounds or banana peels end up in the ground than in organic waste. Dried and incorporated into the plant substrate, they offer your oleander a cheap and organic alternative to purchased fertilizers. However, coffee grounds have an acidifying effect on soil. If your oleander becomes too acidic, the availability of nutrients in the soil is limited.

Lime can help here. And in this case, too, the organic waste can become a treasure trove: just mix it with the soil Fertilization from crushed egg shells as a source of lime. Anyone who uses rock flour to supply their plants with important trace elements can also use it as an alternative fertilizer dare to use liquid manure from plant residues, because rock flour reduces the unpleasant smell of liquid manure and makes it attractive fertilizer variant. In this way, you can give plant residues such as weeds in the garden a useful second use.