When to water orchids is a question about orchid care that can cause the most concern to beginners and experienced growers alike.
A good rule of thumb in this instance is 'when in doubt, don't'! More orchids die from over watering than under watering.
It is impossible to lay down any set rules for watering as there are so many variables.
Some of the more obvious ones include temperature, ventilation, pot size, the age of the potting compost, and the state of growth of the plant.
However, here are a few simple guidelines: 1.
A plant in new compost needs more water than one in compost that has begun to break down making it less aerated.
2.
Small pots dry out more quickly than large ones so will need more water than the large.
3.
Orchids mounted on bark will need to be watered (or at least sprayed) more frequently than those in pots.
4.
A plant in active growth will need more water than one that is resting.
When you can see a new leaf appearing, your orchid is growing.
When there is no sign of any new leaves, the plant is resting.
Some species of orchids hardly rest at all, while others will remain dormant for longer periods.
It is a good idea to do a little research on your particular species to find out when and how long that resting period is.
Those that are resting need little water because their roots can't take it up.
If you over water your plants at this time, you risk rotting their roots.
As far as temperature goes, in winter, once a week to a fortnight may be enough watering for those in pots whereas in summer, depending of course on how high the temperature rises, and the other considerations above, they may need watering up to twice a week.
A good rule of thumb in this instance is 'when in doubt, don't'! More orchids die from over watering than under watering.
It is impossible to lay down any set rules for watering as there are so many variables.
Some of the more obvious ones include temperature, ventilation, pot size, the age of the potting compost, and the state of growth of the plant.
However, here are a few simple guidelines: 1.
A plant in new compost needs more water than one in compost that has begun to break down making it less aerated.
2.
Small pots dry out more quickly than large ones so will need more water than the large.
3.
Orchids mounted on bark will need to be watered (or at least sprayed) more frequently than those in pots.
4.
A plant in active growth will need more water than one that is resting.
When you can see a new leaf appearing, your orchid is growing.
When there is no sign of any new leaves, the plant is resting.
Some species of orchids hardly rest at all, while others will remain dormant for longer periods.
It is a good idea to do a little research on your particular species to find out when and how long that resting period is.
Those that are resting need little water because their roots can't take it up.
If you over water your plants at this time, you risk rotting their roots.
As far as temperature goes, in winter, once a week to a fortnight may be enough watering for those in pots whereas in summer, depending of course on how high the temperature rises, and the other considerations above, they may need watering up to twice a week.
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