Cultivating orchids in your own home takes a lot of tact. In addition to the location, substrate and watering, the addition of fertilizer plays an important role among the maintenance factors. The sensitive flower beauties with the exotic charm want to be supplied with well-dosed fertilizer. Experienced orchid experts repeat again and again that an insufficiently sized nutrient ration can hardly cause damage, whereas an overdose has fatal consequences. It pays to invest a little time studying how to properly fertilize orchids. The following tips for fertilizing orchids are intended to serve as a useful aid.
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Different orchid fertilizers
Conventional flower fertilizer, which is offered in liquid form in garden centers, hardware stores and specialist shops, is definitely unsuitable for orchids because it contains too much salt and nitrate, which can literally burn the roots. It is better to use products that primarily focus on the nutritional needs of the orchids.
Special orchid fertilizer is precisely tailored to the needs of the plant. It contains all the important nutrients, such as nitrogen and potassium to promote growth, phosphorus for beautiful flowers and strong roots or magnesium for a lush green leaf color. As a rule, it is sufficient to supply the orchid with liquid fertilizer when a new leaf or a young shoot appears. Very vigorous orchid species generally receive a ration of liquid fertilizer once a month. To be on the safe side, you should start with around 50% of the indicated dosage to observe the reaction of the plant.
As an alternative to liquid orchid fertilizer, fertilizer sticks are available in stores. These are pressed into the substrate and release the necessary nutrients over the next three months. The effectiveness of this method is a matter of controversy among experts. The advantages are obvious: The use of fertilizer sticks saves time, money and work. The fact that such rods need a moist soil substrate in order to spread should be considered a disadvantage. This is not necessarily the case with the porous orchid substrate. In addition, it is not entirely up to the hobby gardener to control the concentration of nutrients. Anyone who wants to fertilize their orchids properly depends on being able to precisely influence this factor.
Orchid Vital Spray
Since orchids also absorb their nutrients through the leaves, a vital spray was developed. On the one hand, this supplies the plant with additional urea and, on the other hand, brings a beautiful shine to the leaves. It is essential to avoid spraying the flowers during application. Rather, the Vital Spray is applied to leaves and roots until a delicate film forms.
Hobby gardeners who principally use biological and natural products can use the homeopathic fertilizer spray to stay true to this line when caring for their orchids. The well-known manufacturer Neudorff has developed a ready-to-use tonic. This essentially consists of horsetail extract, copper sulfate, sulfur, guano, worm humus and loess. Used regularly, it naturally promotes flower and leaf growth. The resistance of the orchids to diseases and pests is also strengthened.
Cottage lime for a better calcium supply
Apart from the lithophytic genera that grow on rocks, most orchids need additional lime so that they can absorb the vital calcium. Calcium is neglected as a component in a large number of orchid fertilizers. If you want to compensate for this deficiency in your orchids, add 1 gram of cottage lime to 10 liters of rainwater, leave the mixture to stand for 3 to 4 days and dissolve the required amount of liquid fertilizer in it. In contrast to other types of lime, the calcium here is bound to silica and therefore immediately soluble in water. The orchids supplied in this way thank you for this measure with increased root growth. Other types of calcium or calcium nitrate used by professional growers also contain a certain amount of nitrogen, what one would then have to consider when fertilizing. If an orchid receives too much nitrogen, it will cause soft shoots to grow. For a hobby gardener, the calculations and corresponding dosages would be associated with a disproportionate amount of effort.
Aid for better fertilizer absorption
Researchers have succeeded in developing a plant aid that sustainably supports the healthy growth of orchid roots. Since this is accompanied by the activation of the soil bacteria, the absorption capacity of fertilizers is optimized. Root Complex from Hesi is rich in essential nutrients for the sensitive orchids, but does not contain any fertilizer itself, is pH-neutral and does not increase the salt content. Therefore, it is used at the same time as orchid fertilizer. Since Wurzel Complex also reduces the stress on the plants after repotting or planting, the agent is also used on this occasion.
Low-salt irrigation water
In their tropical homeland, orchids are watered by short but heavy showers of rain. Since this rainwater is almost salt-free, there are some arguments in favor of watering and fertilizing the orchids cultivated in the room as well. Experienced hobby gardeners therefore collect the rainwater and store it in a covered basin in which a small water pump ensures constant, light movements. Alternatively, you can also use fully demineralized water or distilled water to dilute the liquid fertilizer according to the instructions. Water that is as low in salt as possible should also be used as pure irrigation water in order to flush any accumulations of salt from the roots between fertilizers. Ordinary tap water is less suitable because it usually has a very high salt content.
Do not fertilize during the break
Since orchids put all their power and energy into the formation of the magical flowers, they need a break from time to time to relax. The first signs that the plant is heralding the dormant phase are withered and falling flowers. In addition, the formation of new buds and shoots is stopped. As long as the orchid is resting and gathering fresh strength, it not only comes to a cooler location, but is watered even more sparingly and no longer fertilized. The end of this phase is determined by the orchid itself and signals this by sprouting again. The time has come for the experienced hobby gardener to put the orchid in a lighter place, to water it again and to support it with the gift of fertilizer.
Properly fertilize popular orchid genera
Basically, a distinction is made between three growth forms. More than half of all genera grow epiphytically, i.e. mostly on the trees of the rainforests, because more light is available here. Orchids in the lithophytic growth form, i.e. on rocks and stones, are less common. The most interesting growth form for enthusiastic hobby gardeners are the terrestrial orchids, which grow on the ground and therefore also feel comfortable on the windowsill. But also some epiphytic and lithophytic growth forms have made it to the top of the popularity scale. Although there are currently more than 1,000 recognized genera and around 20,000 species of orchids, a manageable number has emerged that is particularly suitable for indoor cultivation in the local area.
Paphiopedilum – women’s or Venus shoe
- genus growing on earth
- outside of the rest period in summer, fertilize with every 3rd watering
- In winter, a monthly application of fertilizer is sufficient
- The maximum dosage is the value stated on the package
Bletilla – Japanorchidee
Each of its numerous species follows a growth cycle that is unusually strict for orchids. It grows and blooms profusely in spring and summer, so that during this time it is fed every 2 weeks first with nitrogenous fertilizers and later with phosphorus-based fertilizers. From autumn the Japanese orchid takes a break, which makes further fertilization unnecessary.
Phalaenopsis – moth orchid
- Genus is characterized by a certain blooming laziness
- largely insensitive to fertilizer
- receives some fertilizer every third watering in spring and summer
- every 4 weeks in winter
Brassia – Spinnenorchidee
- in the growing season with every second water fertilization
- no further shoot formation, stop fertilizing until the first flower appears
- then: continue with the administration of special bloom fertilizers until the rest period
Due to its small growth form, this genus is ideal for housekeeping. The heat-loving orchids receive fertilizer every 2 weeks from March to September. As soon as they signal that they are going into recovery mode, fertilizing is stopped.
Cymbidium – tub orchid or scotch orchid
- need unusually large amounts of fertilizer
- in the growth phase every 14 days
- already strong plant, even a small amount of blue grain is good for it
- sprinkle on the substrate in spring
- Sometimes this orchid continues to grow even during the winter break
- also fertilize lightly during this time
- Roots are particularly thin and sensitive to salt
- Plants only receive highly diluted liquid fertilizers
- especially when it is very warm outside
- no fertilizer during the break
Anguloa – Tulip orchid
One of the few genera that can also be cultivated in beds in summer. During this time, she will need a good dose of orchid fertilizer every 14 days. As soon as the first frost approaches, she comes into the winter garden or a cool room, where she takes her break and receives no fertilizer.
- from the Andes of South America
- numerous species that prefer cool temperatures
- a dose of heavily diluted fertilizer every week in spring, summer and autumn
- Mix with water that is as low in salt as possible, preferably rainwater
- Do not fertilize on hot summer days or during the winter break
- produces particularly beautiful and large flowers
- is extremely sensitive to salt
- fertilize every 3 to 4 weeks during growth and flowering
- Dilute at least twice as much as stated on the package
It is rated as an accolade among hobby gardeners if the cultivation of the noble orchids is successful. If you take a closer look at the demands that these natural beauties place on care and fertilization, you will find that it is entirely possible to keep orchids in bloom in full bloom. The most important basic rule is that with these plants less fertilizer is significantly healthier than too much of a good thing. There are numerous special orchid fertilizers available in stores, the contents of which garden enthusiasts can understand much better if they know the nutritional requirements of their preferred orchid genus. With the right mixture, at the optimal time, in the perfect dosage and taking the rest period into account, nothing stands in the way of successfully keeping orchids.