Container growing has lots of advantages. It is flexible, allows you to grow where there is no suitable soil available, and you can move them around at different times of year to suit the weather conditions. However, there is no escaping the fact that anything growing in a pot is going to have a root system that is a fraction of the size it would have it was allowed the freedom to grow in the soil. This means that any plant growing in a pot will definitely need feeding. Most commercial potting composts have some nutrients added, and this will keep your plants going for about 4 weeks. But after this, they will start to run out of steam, and you will need to supplement them.

I have just started making comfrey feed which will come in handy in a few weeks’ time, as my tomatoes are just starting to flower. Although there are many elaborate methods of making comfrey feed, I don’t think you should be put off by thinking that it is a complicated process. All you need is a bucket, and preferably a lid to keep the smell in. I cut down about a third of a bucket of leaves, then added water, just to cover them. It will be ready in about a month. Comfrey is particularly suitable, because it is deep rooting and brings up nutrients from deep down. Also the leaves break down quickly in water. However, that shouldn’t stop you experimenting with other plants. Ideally you want to take anything with softer lush green growth as this will have a higher nutrient content than tougher older leaves which are full of lignin and cellulose that take a long time to break down.

In the meantime, before the comfrey feed is ready, I will be producing my own home made plant feed. Many may recoil in horror at the idea of collecting their own urine, but it contains a good balance of nutrients for plants. Also I think it makes far more sense to use it to feed my tomato plants than flush it away down the toilet to be treated and processed at great expense. It really is closing the nutrient loop. It is too concentrated to be added neat, so dilute in 1 in 5 to 1 in 10.

In the meantime I have one more tip for glasshouse tomatoes: the adjustable tomato string clothes peg system! Wrap the bottom of the string round the base of your plant. Extend the string upwards to the top of the greenhouse, then loop the string over the top of a support, hook or wire at the top. Pull the looped end downwards, then use a clothes peg to clip it to the upwards string. The tomato can be gradually twisted around the string. The advantage of this system is that the position of the clothes peg can be adjusted to slacken the string as the tomato grows, so that the strings don’t throttle the stems as the plants get bigger. Just try it, it’s not nearly as complicated as it sounds on paper once you have a go!

More about Anton...
Anton is a Knowledge Officer at Garden Organic, where he has worked for 16 years. He is looking forward to writing a series of blogs on how to garden using little resources.

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