Anthurium plants in nature are used to grow in well-drained and very good aerated conditions. To obtain the best result in “greenhouse circumstances” we need to have at least the same conditions, or even better. The most important items for a good growth in general for all sort of cutflowers are the following.
1. THE SUBSTRATE
There must be a good growing medium for holding the roots of the plants. In the substrate medium it must be possible to hold enough water, but it must also be with a very high aeration. The substrate must release the drainwater very quickly after every irrigation and it must keep its structure during the time of the culture.
2. THE IRRIGATION SYSTEM
This system must be well calculated and adjusted to the situation. The best system nowadays is a drip-irrigation system, but also a sprinkler system with small capacity sprinklers can be used. The pump capacity must be sufficient, so that on every time of the day there is the possibility to bring enough water to the plants. This water must be with fertiliser and adjusted to the correct pH.
3. THE SUBSTRATE SYSTEM
This is the system in which we hold the substrate. This must be designed to hold the substrate, but in a way that the volume of the substrate for each plant is not too much nor too little. This should be about 6 – 9 litres per plant. When it is more, it means that there can be too much water for each plant which makes it difficult to control the substrate. For that reason it is also better to have a narrow, but high substrate column, so that water passes through all the substrate from above to below. Too much water can also increase the chance of diseases. For the system it is very important to have a very quick drain water discharge out of the system and never any place where there can remain water.
For substrate many different materials can be used, but they must meet the demands of the crop and local circumstances. Normally it is no problem to use a substrate that is available in the area, but it must be of a very good quality. We can analyze substrates and check if they meets high quality standards. Natural substrates (such as coarse peat, cocopeat, perlite) are a good alternative, they give no waste problems after use. In Holland polyphenol foam(=Oasis) is used by most growers and gives very good results. The pH always has to be stabilised before planting.
When growing under a netting system, a shade clothe or similar, it is also important to have an irrigation system for the dry periods, to keep a good growth. When there is no irrigation, the substrate might be too wet in a certain period and to dry in the other parts of the year. The growth of the plants can be most stable and controlled best, with an irrigation system and a waterproof covering above the plants. Nowadays this is the most used solution and it certainly improves the quality of the flowers.
The irrigation will be the best with an in-line drip irrigation with drippers on every 25-30 cm. and with 4 lines in each bed. This means there is an in-line dripper for each plant. When using a sprinkler system the best is 2 lines in a bed with the sprinkles on a distance of 50-75 cm.
The planting distance depends on the variety that will be planted and on the climate conditions of the area. The average situation is six to seven plants per m2, planted in 4 lines in a bed, which are 30 cm. apart from each other. The plant-distance in the lines will be ± 30 cm. and these must be planted in the most economic way.
In general there are 2 possibilities to make the system. The first and most simple possibility is directly on the ground, with plastic liner and sideboards to hold the substrate, or a little into the ground. This must be done mostly by hand and with some slope in the ground to be sure that the drain water-discharge is 100% secure. The installation must be done very carefully, because when the plastic liner is damaged, the roots can go into the soil and diseases can come into the substrate and plants. In colder areas there must also be a root-zone heating system in the substrate, because the temperature may not drop below 20 degrees Celsius. This is an expensive additional system. The volume of the substrate in these beds will be ± 250 litres per linear metre bed.
The other, more used system is the JBH W-system, which has been specially designed for the culture of Anthurium cutflowers. This is a system with 4 small gutters, for 4 lines of plants. In each gutter there is a small drain tube for a perfect water discharge. The JBH system is made of EPS(polystyrene), which gives a good insulation from the ground. It also gives a good protection to the plastic liner. With the JBH system there is no need for an additional heating system for the roots and it also keeps the temperature down in a hot period.
The volume of the substrate in the JBH system is 110 litres per linear metre bed, but of course we also have other sizes with other volumes. We design the JBH systems completely in accordance with the demands of the grower. The lower volume of substrate to each plant gives a much better control and it reduces the total volume of substrate with 50-60%. For each plant there will be ± 8 litres of substrate, which still is more then enough.