Watering Orchids – Orchid Growers Tips
Watering Orchids – Correct Watering
Orchids love contact with water but this experience should be brief. In particular, themust dry off rapidly afterwards.
It is not for nothing that orchids thrive on permeable, porous planting substances which allow water to drain away quickly as through a coarse sieve. This alternating of wetness and dryness will make them feel right at home, as will the alternating daily rhythm of heat and night-time coolness. Waterlogging will kill off any orchid!
The best water for watering
Water should always be at room temperature, slightly acid and soft. With the exception of some lady’s slipper species, all orchids hate lime. Rainwater or melted snow in the winter is usually soft, but with increasing atmospheric pollution these days they are rapidly losing their good qualities in many areas.
Collect rainwater, allow it to run through a paper coffee filter and then allow it to stand for a few days. You can also purify rainwater using household water filters.
If you use mains water for watering, you should check the acidity content (pH value) and the hardness of the water.
The acidity content is easy to measure with a strip of indicator paper (obtainable from chemists or aquarium suppliers). The values are expressed in degrees of pH. The scale extends from 1-14, and the neutral reading is in the middle at 7; all figures below 7 are in the acid range; all figures above 7 are in the alkaline range. Orchids prefer weakly acid water with a pH value of around 5 or 6.
The hardness of the water can be ascertained by enquiring at your local water authority.
It is measured in degrees Clark: 0-10 = soft water 11-20 = medium hard water 21-38 = hard water
Orchids can tolerate water with a hardness degree of, at most, 13 degrees Clark, although a very few can cope with values up to 15 degrees Clark. If your mains water value is above this, you will have to soften it.
How to soften water:
In the case of medium hard to soft water, a few drops of lemon juice will be sufficient to soften it.
Harder water has to be properly treated. (All preparations and gadgets are obtainable in the gardening trade).
- With water-softening agents in tablet, powder or liquid form. These will precipitate lime and other undesirable substances from the water. If you decant the water carefully after several hours, the lime deposits will settle at the bottom of the container.
- Ion exchange fertilizers are able to exchange substances that produce hardness for those that produce softness.
- Using a watering can with a filter attachment containing ion exchangers that get rid of lime and chlorine.
- Fill a small linen sack with peat and suspend it in a bucket of water.
- Boil the water. This will remove limescale. Unfortunately, it will also get rid of most of the oxygen.
Immersing instead of watering
Orchids in hanging baskets are not easy to water as the water tends to run out. Immersing the entire container in water will do the trick just as well. Hang the basket up again as soon as the water has drained out.
Whatever type of mains water you have, it may contain chlorine which orchids have difficulty in coping with. To be safe, allow the water to stand overnight before using it. Using water from water-softening gadgets can also be risky as salts that can be harmful to orchids may be present.
How often to water
This will depend on many individual factors:
- on the type of growing medium, which will absorb more or less water depending on its consistency
- on the plant container being used; orchids in plastic pots will not dry out as fast as those in clay pots. Plants in airy hanging baskets or growing on branches will dry out quickest
- on the humidity level; the higher this is, the less often you need to water
- on the temperature; the warmer and sunnier the weather, the quicker water will evaporate
- air movement; windy conditions in the plants’ summer quarters or a ventilator in a window will cause the growing medium to dry out faster
- on the growth of the plants; an orchid that is going through a growth phase and is producing many new shoots will require more water than a plant that has finished growing and is conserving energy for the ripening of its bulbs and for forming flowers. If you give too much water now, the orchid will produce masses of leaves instead of flowers.
The finger test:
Push a finger fairly deep into the growing medium. If it feels dry, give the orchid a vigorous watering. Allow the pot to drain off well afterwards. The growing medium should not be allowed to become too dry or it will have difficulty absorbing water. If the medium feels moist and slightly cool, do not water.
How to water orchids
Orchids are best watered from above so that the growing medium is moistened all through. Do not allow water to run over the plant itself. Orchids that are tied to branches or installed in hanging baskets can be dunked in a bucket of water several times (see illustration, left).
Watering and spraying are best done in the mornings. This will allow the plant enough time to dry off before the inevitable slight drop in temperature towards evening or when the heating is turned down for the night. This method will prevent a harmful drop in temperature due to evaporation in the root area.
Watering orchids during absences
All irrigation systems currently on the market work on the principle of capillary action. Water conductors are inserted into the compost or planting medium, in the shape of cones, wicks, felt discs, mats or absorbent wood. These constantly absorb water from a reservoir to which they are connected. The larger the reservoir of water, the longer the orchid plants can be left to their own devices. However, this system is not entirely problem-free with such sensitive plants as orchids.
Watering orchids during vacations
Using a heavy-duty needle, draw an absorbent wick up through the drainage hole at the base of the pot and through the compost. Thread the wick through a drinking straw, then arrange it on the surface of the compost and cover it with a thin layer of compost. If the plant has a compact root system, remove it from its pot beforehand. If the lower half of the orchid’s compost is coarse and well-aired, this method will function even better.
I have experienced satisfying results with such systems. The inventor of this method keeps thousands of orchids and yet is able to go off on holiday for three weeks at a time.
Mistakes in watering orchids
Unfortunately, mistakes in care do not always become immediately obvious. Often it is already too late to put things right once they are noticed. You may have either watered too often or too much if:
- the leaves go limp, drop off or turn yellow
- the roots are decaying
- growth ceases.
You have given too little water if:
- the pseudo-bulbs shrivel
- the roots turn brown and wither
- the leaves go limp, drop off or turn yellow.
Watering orchids in the summer
In conditions of constant high pressure, orchids will rapidly dry out and may have to be watered daily. During periods of damp weather, on the other hand, the growing medium may stay wet for too long. If there is continuous rainfall for longer than two days and there is no prospect of an improvement in the weather, it is preferable to place the orchids beneath an overhanging roof or something similar.
Orchids hanging in tree branches can be placed on a patio wall that is shaded from direct sunlight. It is very important never to place orchid pots directly on the ground or on a table as it is absolutely essential that air is able to circulate beneath the pot and that even the slightest bit of waterlogging is avoided. In the case of large containers, place a few bricks underneath them, and place small pots on a lattice-top table or on a grid.