Are you worried about watering your orchids when you travel? Or, do you tend to overwater them? Try growing your orchids in self-watering pots.
A self-watering pot can supply constant moisture to the roots of a plant automatically through a wick by drawing water up from a reservoir to the medium. It is easy and convenient in keeping the orchid moist, not only saving us the trouble of watering but also to prevent overwatering.
This article will show how these pots work, the pros and cons, and how to make one yourself or where to buy one online.
1. How self-watering pots work for orchids: “wick watering”
A self-watering pot consists of an inner pot with a drainage hole on the bottom, placed inside another pot which has a water reservoir at the bottom.
A “wick”, basically a string, is placed inside the inner pot, going from somewhere close to the orchid roots out of the pot through the drainage hole to the reservoir of water below.
In an automatic watering pot, water is absorbed by the wick submerged in the reservoir and is pulled upwards to the medium when it is dry, thus maintaining the medium constantly moist.
2. Differences between wick watering & semi-hydroponics
The two are quite similar. They both have a reservoir of water at the bottom where water will be wicked upwards. Also, they both use LECA (Lightweight Expanded Clay Aggregates) balls as the orchid medium.
But the differences between the two are actually quite big, fulfilling two different purposes.
In a self-watering system, you do not need to water the medium but only keep the reservoir filled with water. Water is absorbed and pulled upwards from the reservoir to the medium. And the reservoir is outside of the pot, thus an outer pot is needed to hold the water. Most importantly, it is an automatic watering system that the plant does not need to be watered for a long period of time, even a month, as long as there is water in the reservoir.
On the other hand, for a semi-hydroponics system, you need to water or actually flush the media and let the water run downwards going out of the drainage holes. The drainage holes are not only at the bottom of the inner pot, but also on the sides to help the water escape quickly. Although the media would be kept moist as water is wicked up by the media, the media needs to be watered and flushed every few days or every week.
3. Pros of self-watering pots for orchids
Self-watering pots work effectively for many orchids, including the many species of Phalaenopsis, Cattleya, Oncidium and Dendrobium. The advantages of self-watering pots are convenience, preventing the roots from drying out and preventing overwatering.
- This method can keep the medium, even the top of the medium, constantly moist (but not too damp) for as long as there is water in the reservoir.
- It is a very easy and convenient system because it can support an orchid for as long as a month without watering, depending on how much water there is in the reservoir. This saves the hassle of watering every few days and it is also a very convenient way for those who travel or do not have time to water.
- It prevents overwatering and thus root rot, which is a common mistake for orchid growers. This is because water is not poured into the medium but absorbed upwards through a wick submerged in the reservoir.
- Using an inorganic medium (e.g. in the form of LECA) means that it would not decompose and you would not need to unpot the orchid, change the medium and disturb the roots unless the plant outgrows the current pot.
4. Cons of self-watering pots
Since the self-watering pots work fairly well in keeping the roots moist, they are great in a dry environment and ideally a hot one. But, if you live in a humid and cold environment, the following aspects can be drawbacks:
- The medium in self-watering pots is constantly wet, which can be a problem for humid environments.
- Most of the outer and inner pots aren’t transparent that one may lose touch with the hydration level of the plant and root health
- Also because of the non-transparent outer pot, algae can grow in the reservoir
- Self-watering pots can be quite expensive, especially if you want to use more than a few pots. More about that later.
- There is a limited choice in terms of pot design or materials for purchase or for DIY. Most of the commercially available pots are plastic. And a DIY setup may not look the best for some people.
The problem associated with the non-transparent pots can be mitigated using a DIY solution: by making the pots yourself using transparent outer and inner pots. More about this later.
5. How to make a self-watering pot (DIY)
Outer and inner pots
- The inner and outer pots can be created by cutting up a half-gallon or one-gallon soft drink bottle, with the upper part placed inverted inside the other with space below. Or, use a clay pot as the inner pot, placed above a tray of water. Clay is a good material because it would help the medium breathe and not trap too much water like plastic. Opaque pots also have their benefits for allowing you to check on the roots easily and to prevent algae from growing in the water.
- Make a drainage hole at the bottom of the inner pot.
- Use a thread of micro fiber cut from a new clean mop. A synthetic thread is better than a cotton string or even sphagnum moss because it would not decompose inside a constantly moist medium.
- Place the thread through the drainage hole going up to where the orchid roots are. Fill the inner pot with an appropriate orchid medium.
- Use LECA (Lightweight Expanded Clay Aggregates) balls as the orchid medium because it is inorganic and would not decompose even though the medium is kept moist constantly.
That’s it! Very easy, right?
Check out the following video for some examples of DIY self-watering pots.
6. How to fertilize orchids in self-watering pots
To minimize salt build up, fertilizing orchids in self-watering pots can be done easily by using reverse osmosis / distilled / rain water with a very weak fertilizer (1/6th strength – more about fertilizing orchids here). In fact, there is no need to keep adding fertilizer as long as the reservoir still has water with fertilizer.
To avoid salt buildup, soak and flush the inner pot with water once every month.
To sum up, self-watering pots are a great sustainable solution for watering orchids without the hassle of having to water them for up to a month. It also prevents the problem of underwatering or overwatering. The only drawbacks would be the one-time cost of buying or making the pots yourself and also the few choices for pot design. But the pros definitely outweigh the cons.