April can be a strange month weather wise. One minute the sun is blazing, the next you might be enjoying some good old April showers. In a polytunnel, of course, a gardener can escape the weather when it is not ideal. But being under cover does mean that you will have to think more carefully about watering your plants, since the April showers will not do it for you. Getting it right when it comes to providing water for your growing plants is one of the key ingredients in any gardener's recipe for success. Here are a few tips to help you get it right:
A gardener should always try to make use of the natural resources at their disposal. Rainwater collection is easy and simple – all you need is large butts or barrels attached to the down pipe on your home, garage or shed. Not only is collecting rainwater an ethical and sustainable choice, it is also better for your plants than treated mains water. When watering inside your polytunnel, or elsewhere in your garden, try to use rainwater rather than tap water whenever possible.
An irrigation system, especially an automated one, is practically a must-have for commercial growers. Even for home growers, the savings in time that come from not having to water by hand, sometimes every day, can definitely be worth it. There are many different options when it comes to irrigation systems, so it is a good idea to check out all the options. Consider your options for linking in such a system to your rainwater harvesting. April is the month when watering in your polytunnel will definitely need to be stepped up, so it could be the perfect time to think about installing a watering system.
Even if you only have a small polytunnel and do not need an automated irrigation system, you will still need to consider how to provide your plants with water when you are away from home. If you have a lot of containers in your polytunnel, plastic water bottles placed upside down in the soil of your containers and filled with water will slowly release that water for the use of your plants while you are away. This is a cheap and efficient way to create a home-made drip irrigation system. Clay pots can also be placed in soil and will gradually release water as and when it is needed. A fabric wick, with one end in a container and the other in a water-filled bucket can also provide moisture for plants through capillary action.
All the above methods can help to make sure you have the most of the water that you have. But in some parts of the UK, water can be in such short supply during the spring and summer months that is a good idea to do what else you can to reduce water use. By placing thick, organic mulches and trying to minimise the amount of bare soil in your polytunnel, you can conserve water and help retain moisture for the use of your plants. A good quality compost, chopped and dropped leaves such as those from Russian comfrey, leaf mould or even grass clippings can all make good organic mulches for certain crops. Make the most of the biomass (organic material) that you have to hand.
However you water your polytunnel, it is important to consider where the water is needed. Most plants should be watered carefully at soil level and you should take care to get as little water on the foliage of your plants as possible. The needs of each plant are different and some will need higher humidity and more water than others. Try to take into consideration the differing needs of different crops and aim to provide water where it is needed with a thoughtful approach, rather than just drenching the lot.
