Especially when you have a greenhouse some distance from your house or the nearest tap, watering can be a bit of a chore. Carrying watering cans full back and forth always encourages you to skimp and without enough water you won’t get a good crop.
For example,irregular watering is terrible for tomatoes, causing split skins and blossom end rot.
Automatic Greenhouse Watering Systems
There are some useful aids that can automate things to save your time and ensure your plants get enough water. Using some automatic water reservoirs you can even take a few days off knowing your plants are safe.
I particularly like drip irrigation systems because rather than the plant cycling through drought and flood you can evenly water throughout the day. Even without mains water being available you can use a bag drip watering system.
As any gardener knows, once it has dried out compost is a devil to get wet again and a drip system will not only prevent this but will slowly re-soak the compost so it absorbs the water if it does happen.
When it comes to manual watering, don’t forget the humble gravel tray. A proper gravel tray is a vital tool for propagating and growing on in pots in the greenhouse. The gravel tray has a thin layer of gravel placed into it which serves two purposes:
First the gravel keeps the pots from sitting directly on the base which could prevent excess water from draining out and result in water-logged compost killing the plant
Second the water below the top of the gravel helps to increase humidity but not in excess which could encourage fungal diseases.
Watering in a plunge bed
A deep gravel tray can also be filled with washed damp sand and used to plunge pots into. This prevents them drying out and controls temperature to a degree. Use plastic rather than clay pots and screw them into the sand.
This is simply matting which distributes water through capillary action. One end is placed in a reservoir tank of water or the matting is manually watered from a can.
The seed trays are placed directly onto the mat. This gently waters the compost which is drawn up from the base.
Water Type & Temperature
Some prefer to use tap water in the greenhouse to avoid the possibility of it carrying any fungal spores from the air or other disease problem. On the other hand tap water varies in different areas and can be extremely alkaline which is not good for some plants.
At simplest, fill watering cans after use and leave them in the greenhouse to come up to the same temperature as the air. Better still, especially considering a good daily watering in the summer can use 100 litres, is to put a water butt actually in the greenhouse. I use a slimline 100 ltr water butt on a stand.
Greenhouse Growing, Coldframes etc. Further information
- Best Position for a Greenhouse – Where to Site a Greenhouse
- Wooden Greenhouses Compared to Aluminium
- Greenhouse Heating Guide – Various Types Reviewed
- Second Hand Greenhouse – Buying, Dismantling and Re-building a Greenhouse
- Greenhouses in High Winds – Protect and Survive!
- Greenhouse Accessories for Heating and Ventilation
- Fitting out the Greenhouse: Shelving, Staging & Greenhouse Benches
- Watering the Greenhouse – Equipment to Help Greenhouse Watering
- Portable Greenhouses – Patio Greenhouses and Allotment Greenhouses
- Managing the Hobby Greenhouse
- Cold Frames – Uses of Coldframes – Types of Coldframe
- How to Build a Cold Frame for Free!
- An Indoor Greenhouse – The Dewpoint Propagating & Growing Cabinet
- Choosing a Greenhouse – What Greenhouse to Buy