The right care of hydroponic plants is no problem.
Although problems might also occur here, they are easier to prevent compared with the care of soil plants.
In general plants should be watered with lukewarm water.
The water is poured over the expanded clay at any spot, until the level indicator reaches the 1/2 marking (optimum).
Exceptions: Plants with great need of water and/or bright places can be filled up to the upper marking. For plants at darker places with lower needs for water the level indicator should only be filled up to the (min) marking.
The watering interval for hydroponic plants depends on the size of the planter and lies at 2-4 weeks.
If the plants are watered too often there is the risk of root rot. If you want to make it particularly well, then wait one to three days for small planters and three to five days for large planters until refilling at minimum level. This improves the ventilation of the substrate and thus the oxygen supply to the root area.
With Longtime substrate attention should be paid after the first growing phase that only the watering tube of the water level indicator is used for refilling. (Soil plants need to get used to the new climate in Longtime substrate for some weeks - thus in the beginning the plants should be watered near the root bale to assure that the plant is not getting dry. After a period of about 2 months (activation of capillary effect) only the watering tube should be used for refilling anymore. The watering interval with Longtime substrate is approx. 6-8 weeks.
Use the Moistick®/Bloomer from Luwasa or a mobile moisture sensor measuring stick for the ideal indication of moisture. If the plants are watered too often there is the risk of root rot. Water level indicators only show if water is available in the planter and often have the disadvantage that they get stuck. Furthermore different manufacturers sell more and more mineral substrates which quickly absorb the refilled water. In this case the water level indicator would show little to no remaining water already shortly after watering and would confuse the consumer and might lead him to refill the planter again. This inevitably leads to overwatering and the plants will die. Even the "green thumb" won't help with mineral substrate, as the moisture in the substrate can't be determined with the fingers.
The liquid hydroponics complete nutrition has to be added to the water according to the dosage information on the packaging. If the instructions of the manufacturer are kept there is no risk of excessive fertilisation. If the growth of fertiliser-demanding plants (e.g. philodendron, ficus trees) shall be stimulated, the dosage can be doubled - but not for plants sensitive to salt.
Ion exchange fertilisers (available as fleece bag or granulate in cans from "Longtime nutrition Luwasa") are more expensive compared to liquid complete nutrition, but they offer inevitable advantages for hard water and reduce the care effort to a minimum. Vigorously growing plants maybe use up their nutrition supply earlier, modest plants only later. Also here the dosage and using instructions have to be adhered to.
Pruning the plants:
Of particular importance is the pruning of quickly and high growing plants already at the time when the leaves are still on the base. Thereby even the growing shape can be significantly influenced.
If possible the plant is cut back to a leaf axis, where then below the cut branches will grow out of the buds. If the plant is often pruned, it will be compact and bushy. For climbing plants, e.g. philodendron, at least three shoots should be present per planter. In this way only the highest shoot has to be pruned and the smaller shoots give the plant also at the basis a great appearance. Also older plants with trunks, which are getting too massive and have no leaves anymore, can be cut back to the wood. But it takes months until buds in the wood sprout again. The best time for pruning is spring and summer.
Repotting in larger planters:
When repotting small planters the old insert always has to be removed. In case the bale is very rooted the pot eventually has to be slit from the bottom. All old and rotten roots and root rests as well as dirty expanded clay have to be removed from the root bale.
Before repotting the lowest third of the pot is filled with expanded clay.
The roots of the plants are shortened so that they fit in the upper two thirds of the pot.
After repotting the plant needs to be watered with lukewarm water without nutrients. Only at refilling the complete nutrition is added in the prescribed dosage. Also in other aspects careful handling is required for some weeks: The plant should under no circumstances be exposed to direct sunlight, also draught should be prevented. The leaves should be occasionally sprinkled with water. If too many roots had to be cut the plant needs to be protected against great evaporation by means of a plastic cover.
Pests and diseases:
Soil pests or fungal diseases in the root area usually not occur in hydroponics. Nevertheless, if this should once be the case common insecticides or fungicides, which are also used for soil-bound cultivation, can be used. The mixture prepared according to the instructions of the manufacturer is sprayed on the expanded clay until the root bale is wet, but without causing an excess of liquid which will get into the nutrient solution. If this happens despite remaining cautious, then the nutrient solution has to be immediately drained and replaced after application.