Making self-watering containers

With the ever increasing cost of food many people are turning to growing their own fruit and vegetables. If you have a garden then it is quite easy to turn over a small part to veg. If you don't have a garden then think about container gardening.

Containers can be any size that fit the space you have available. These days they are generally made from plastic which is fine up to a point but I would never use a plastic container that is not 'food grade'.

There are lots of pots and buckets, used for transporting food, going for free or sold for very little. They have usually contained catering sized deliveries of things like mayonnaise.

Click on any image to enlarge

Lettuce in a fish box
Supermarkets also throw out huge numbers of polystyrene fish boxes. The fish are packed in ice to keep them fresh and then transferred to refrigerated displays in the store. The boxes are used once then dumped! I have used fish boxes to grow lettuce. All that was needed were holes in the bottom for drainage and some peat free compost.

One of the BIG drawbacks of container gardening is the need for constant watering. Until now! A recent post on the blog highlighted a new idea from the US. It is so simple it is just astounding. See the entry here.

The containers have a water reservoir in the bottom with drainage holes about 50-75mm (2-3inches) up the side of the container. Gravel is used to fill the bottom up to the level of the holes. Compost is added on top.

I liked the idea so much I decided to have a go at adapting some old water troughs left over from a project. It took about 15-20 minutes to make and fill each container.

The first step is to drill some holes about 50mm from the bottom of the container. I used a 10mm drill and spaced the holes about 250mm apart.

Then the container was filled with gravel up to the levels of the holes.

At this point I filled the trough with water.

And then added the peat free compost.

All that was left was to plant out some plants grown from cuttings collected from a bag of ready to eat watercress.

Watercress  with roots down to the gravel                                           The trough fully planted

                          Troughs sown with mixed salad seed

I also sowed some smaller troughs with mixed salad seeds and one with parsley. The salad germinated in 5 days.

That's it! All you need to do is periodically add water until in runs out of the holes and don't forget to feed the plants. This year I will use home made comfrey liquid fertliser diluted 1:20 with water.

Here is the large lettuce trough just 24 days later. We are using the thinnings every day.

If you do have a go please let me know how it works and send some pictures.