We clear up misunderstandings and provide clarity for you.

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We clear up misunderstandings and provide clarity for you.

If hydroponic plants or Longtime system plants are not correctly growing or even die, then the cause is for sure not the system but the wrong choice of plants or locations or a mistake in care. Often the reason is a longer absence, in which often an indoor climate occurs, which is unusual for plants. The reasons are among others:
- too large temperature and light variations
- closed shutters or slat blinds (lack of light)
- too frequent or rare ventilation
- too frequent refilling
- wrong application of plant sprays
This chapter shall help to find out the causes for failure. If they are known and eliminated, an improvement is in most cases immediately visible.

The plant is not growing

Reason: Most likely the wrong choice of plants or locations or rather a lack of light or nutrients. Often there is also the mistake that water is continuously refilled if the plant is not growing in the opinion the more water the better.
How to do it right is described in the section "Ongoing care".

Lack of light

The leaves are falling off, the stem between the leaves is long and thin, young leaves are long and thin, much smaller than usually and often deformed (e.g. lacking leaf splits in philodendron pertusum). Occurs often where shutters or curtains are also closed during the day or if balconies, large trees, neighbouring buildings etc. heavily influence the light entry in a room. Often also the distance between plants and windows is too high. Special plant lamps allow also in dark rooms a good growth.

Lack of nutrients

Often nitrogen deprivation. Old leaves turn yellow and fall off, young leaves turn yellow-green.

Leaves turn yellow

The reasons therefore are manifold. Often accompanied by additional symptoms which allow a detailed diagnosis of the reasons, see e.g. lack of nutrients, improper use of chemical sprays, pest control, lack of light.
If a change of position takes place, which means also during the first time after the purchase of a plant, it is absolutely normal that some leaves at the basis turn yellow. This happens as the plant needs to get familiar with the new location. Also at the beginning of heating periods and if longer foggy periods in winter occur a plant may grow yellow leaves.

Too much light

Leaves are bleached by excessive sunlight and can show signs of burning. Occurs in shadow plants which are placed at sunny south-facing windows and thereby exposed to direct sunlight. This can be prevented by shading in the midday hours. For sunny south-facing windows special succulents, cacti and other plants with high light requirements are suitable.

Leaves turn black

Reasons: Undercooling of leaves due to too low temperatures, often a dual effect with a lack of light; too high water level.
In yucca plants often brown leaf tips are visible - this is in many cases caused by too high water levels - also the opposite (lack of water) can be the case in plants. This has to be checked from case to case. In particular for very valuable plants it makes sense to consult a professional. Here we can recommend our affiliated company Luwasa greenstyling. Click here for the website: www.greenstyling.ch

Leaf necrosis

Leaves start to die off or dry on certain spots.
Reason: Pests, excessive fertilisation, chemicals, too dry air.

Too dry air

An air humidifier helps in this case; cut off the dried parts of the leaf with a scissor closely along the still healthy parts.
Excessive fertilisation: Also dying of the roots and in severe cases also the death of the plant. Caused by excessive fertilisation with common types of fertilisers or use of soil-bound cultivation fertilisers, which are unsuitable for hydroponics. It helps to immediately drain the nutrient solution and to refill the planter with pure water.
Gaseous substances that harm plants:
Cause brown to yellow leave edge necroses. In cases of strong emissions the leaves can fall off green or dry within days or even hours. Usually necroses only occur on old leaves after weeks or months without affecting young leaves. At particular risk are all soft leaf plants such as e.g. ficus benjamina and repens and plants in new buildings or in buildings which are renovated. Some chemical substances, which are nowadays used in construction, are harmful for plants over a longer period of time.

Leaves fall off

Reasons: Either a lack of light or nutrients or pest infestation, improper use of chemical sprays or too low temperatures.
Pest infestation: Very versatile patterns of damage, which often can only be recognised and diagnosed correctly by a specialist: Leaf discolourations, leaf curling, necroses (partial or complete dying of leaves). The most common pests are mealy bugs, aphids, red spiders and thrips.
Improper use of chemical sprays: Within one or two weeks after the first treatment the leaves slowly turn yellow, until they are finally only green at the leaf veins anymore. Often this damages occur also due to wrong use of leaf shine and plant protection.
Too low temperatures: Often accompanied by root rot, finally leads to the entire plant's death. Particularly at risk are plants requiring heat such as ficus bejamina, in poorly heated rooms or at draughty locations near entrance doors in the cold season. Leaf damages due to undercooling can occur due to abundant ventilation of rooms in the cold season, whereby the leaves turn black. For cold locations only suitable plant types shall be used or a floor heating shall be installed below the planter. Planters on cold stone floors necessarily need an insulation sheet to assure that no temperature bridge occurs. If no additional heating is possible, then always a low level of water shall be maintained, i.e. the expanded clay shall be sprinkled with water once a week.

Plants are wilting

Either too less or too much water.
Too much water: In hydroponics and Longtime substrate it is a common mistake of beginners who want to do it "particularly well" and always refill although there is still moisture or water in the planter. Leads to rotten roots and wilting plants. In each hydroponic planter the water reserve should be used up at latest after three to four weeks. If this is not the case too much water is refilled and there is the danger that the breathable roots will die due to a lack of oxygen. If once to much water was refilled the plant is not lost: Drain or empty the nutrient solution immediately and let the planter dry (2-3 days) before refilling again. In the beginning only water gently and without adding nutrients, not more than 1cm above the minimum marking of the water level indicator.
Sometimes the reason for rotting roots is also a defective water level indicator. In small planters the water level indicator can be removed and controlled in a glass of water. If it is blocked by grits of ion exchange fertiliser or roots, wash the water level indicator with water. In large planters the scale of the water level indicator can be elevated and the floater has to be removed. If the floater ball is filled with water the water level indicator needs to be replaced.
Too less water: Occurs only rarely, as even after completely drying of the nutrient supply in expanded clay there is still moisture for some days.

Root rot

The most common reason is too much water, but also too low temperatures. In cases of excessively rotten roots it is the best idea to take the plant out of the pot, cut off the rotting roots and to repot the plant in fresh expanded clay. If all described measures provide no help it also might be that the hydro-gardener, from which the plant was bought, made something wrong. In particular succulents, such as e.g. yucca, sansevieria, different cacti etc. are often planted too deep. In the market garden this is not important, as there are ideal conditions concerning light, warmth etc. Only at poorer locations the mistakes appear, to the disappointment of consumers.
If plants are not growing properly despite all care then get in the full sense of the word to the bottom of things and examine the root area more closely. In case the root bale is still covered with soil or another unsuitable substrate it is recommended to lodge a claim in the shop where the plant has been bought. You not only do yourself, but also the dealer and hydroponics a huge favour!
When buying hydroponic plants you should take care that they are well rooted. This can be recognised by white absorbent roots which grew through the slots of the insert. Brown and soft roots are often not alive anymore and indicate a mistake in cultivation.

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