It almost doesn't matter where in the country you live or the property you are living in because there is almost always at least one spot in the sun that can accommodate a single grow bag. In one fail swoop the ‘grow bag’ revolution made it possible for the ordinary person to successfully grow fresh produce at home, irrespective of whether they had a garden or not.

Such is the culture of the grow bag that most amateur gardeners including a fair number of professional gardeners have an almost mythical belief in it’s capabilities to grow traditional greenhouse crops. With regards to growing tomatoes, if you have no ground in which to plant them in then clearly using a grow bag is your best option, but if you have good quality soil available should you still use the bag or put your trust nature and plant your tomatoes in the ground?

As a native of the South American rainforests, the normal dispersal of tomato seed would begin with its consumption by wild animals or the local indigenous peoples. The digestive process helps to strip the seed of its jelly like coating which contains specialized chemicals that inhibit the seeds germination. After a few hours the seed is returned to the soil along with a dose of natural fertilizer. With the heat of this environment combined with high levels of rainfall, the tomato seeds will germinate within a couple of weeks, making full use of the nutrient rich soil that has been fermenting below them.

For growing outdoor tomato varieties horticultural practice mimics nature as it is usual to prepare the soil before hand, digging in plenty of organic matter or well rotted farm manures. This is fantastic for the crops flavour as it has abundant supply of nutrients - both macro and micro - readily available within the root environment. Without the required range of nutrients, the tomato 'fruit' will be unable to manufacture the proteins, enzymes and pigments etc. that give us that rich and characteristic 'tomatoey' flavour organic gardeners strive for. Compare this to the grow bag which in essence it a small bag of sedge peat which holds no real nutrients of its own.
Sedge peat differs to moss peat in that it becomes greasy and compacts easily but it doesn't create a good open environment for root development. This is why all peat-based multi-purpose and specialist composts will contain moss peat and not sedge peat. It is however very cheap and as mentioned before, like moss peat it has no nutrients of its own which is why all grow bags must be supplemented with liquid feeds on an almost daily basis throughout the growing season. The problem with this is that the only nutrients that are available to your plants are the ones supplied by you.

Is this really a problem, well it is when you consider the ‘Law of limitations’? With regards to available nutrients a plant cell can only grow to the limits of its lowest available nutrient. This means that there may well be plenty of nitrogen, potassium and phosphates within the root environment, but if there is a shortage of calcium for example – a nutrient vital for the formation of plant cell walls – the cells within the tomato fruit will only grow so big until the cell walls collapse due to calcium deficiency resulting in catastrophic cell death. This is exactly the situation that occurs when tomatoes fruit suffer from blossom end rot.

So which is better for growing tomatoes, grow bags or soil? At the end of the day tomatoes will always taste better in the ground but be aware though that constant cropping in the same soil can bring serious problems such as corky root, wilt and eelworm. To avoid this you would need to consider soil sterilisation, or change the soil every few years digging out the old soil and replacing it with humus rich, loamy soil from a part of the garden that has never cropped potatoes. The reason for this is that both tomatoes and potatoes are from the Solanaceae family (compare their flowers) and you may inadvertently transfer blight spores with infected soil. To continue the argument, the problem with growbags is that they limit both the size and the flavour of your crop, however they are convenient.

At the end of the day the choice is yours, but perhaps the most important thing here is that you do get a choice.

For related articles click onto the following links:
How to Grow Giant Tomatoes
T and M: How to Grow Tomatoes

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