Tomatoes

Tomatoes 2000

Some background

A professional grower will aim to produce around 50 kg of glasshouse tomatoes per square metre. That is equivalent to 500kg for a 12 x 8 foot glasshouse. Clearly the professional starts early in the year (December /January) and produces for a long season (to October/November) and it would be difficult to apply the same expert growing methods at home. Nonetheless, most amateurs probably fail to get anywhere near the potential of the tomato plants used either in terms of yield or in terms of quality. Yields can be low and Blossom End Rot (BER), usually blamed onto irregular watering, seems to be familiar to many home tomato growers (it causes blackening of the tomato centre underneath the fruit ie opposite side to the stalk).

Tomatoes are often grown in peat-based growing bags in a greenhouse. We see what happens if you use different volumes of compost, compost diluents and fertilisers and take a look at a hydroponic method for comparison.

What we tested

Typically three plants are grown in a growing bag containing a peat-based compost, plants are watered when required and a liquid feed applied through the summer. What could be wrong with such a simple method?
We decided to grow tomatoes in large containers and look at three main factors:

Volume of compost
- Three plants in the average growing bag means around 10 to 12 litres of compost per plant (unless the roots overlap?). Does it help to increase the volume of compost per plant?
Type of compost
- The three basic needs of the tomato root system are air, water and nutrients. The particular qualities of peat, bark, soil, sand and other growing media determine just how the air, water and nutrients are supplied to the plant. Can we improve the performance of a peat-based compost by mixing in different materials? We looked at soil+grit and perlite as diluents.
Fertiliser/nutrient levels
- Leaving aside, for the time being, the balance of NPK nutrients used (see the Bonanza Bolero Marigold game elsewhere on this site) more or less fertiliser/nutrients should make a big difference to the way the tomato grows. But its not quite that simple because a well-nourished tomato plant can produce lots of leaf and few tomatoes: a bit of a waste of time since its not a particularly beautiful plant, even when it has lots of leaves. So is the use of extra fertiliser worth the trouble and expense?
Keeping it simple
- What about trying a simple hydroponic method of growing tomatoes? Can you get reasonable yields and does it have any effect on problems such as BER?

Home

No doubt the experts among you will feel that you know the answers to these questions. The inexpert will possibly have found it all too complicated to even care. However a lot of gardeners try to grow tomatoes - so, instead of trotting out all the traditional expert recommendations (which may or may not work) we tested a few ideas and you can see the results. You can then make up your own mind whether any of the ideas tested have anything to offer.

The trial started in May 2000 and carried through into September/October.

Details of the trial

	Tomatoes 2000
Some background	A professional grower will aim to produce around 50 kg of glasshouse tomatoes per square metre. That is equivalent to 500kg for a 12 x 8 foot glasshouse. Clearly the professional starts early in the year (December /January) and produces for a long season (to October/November) and it would be difficult to apply the same expert growing methods at home. Nonetheless, most amateurs probably fail to get anywhere near the potential of the tomato plants used either in terms of yield or in terms of quality. Yields can be low and Blossom End Rot (BER), usually blamed onto irregular watering, seems to be familiar to many home tomato growers (it causes blackening of the tomato centre underneath the fruit ie opposite side to the stalk). Tomatoes are often grown in peat-based growing bags in a greenhouse. We see what happens if you use different volumes of compost, compost diluents and fertilisers and take a look at a hydroponic method for comparison.
What we tested	Typically three plants are grown in a growing bag containing a peat-based compost, plants are watered when required and a liquid feed applied through the summer. What could be wrong with such a simple method? We decided to grow tomatoes in large containers and look at three main factors: Volume of compost - Three plants in the average growing bag means around 10 to 12 litres of compost per plant (unless the roots overlap?). Does it help to increase the volume of compost per plant? Type of compost - The three basic needs of the tomato root system are air, water and nutrients. The particular qualities of peat, bark, soil, sand and other growing media determine just how the air, water and nutrients are supplied to the plant. Can we improve the performance of a peat-based compost by mixing in different materials? We looked at soil+grit and perlite as diluents. Fertiliser/nutrient levels - Leaving aside, for the time being, the balance of NPK nutrients used (see the Bonanza Bolero Marigold game elsewhere on this site) more or less fertiliser/nutrients should make a big difference to the way the tomato grows. But its not quite that simple because a well-nourished tomato plant can produce lots of leaf and few tomatoes: a bit of a waste of time since its not a particularly beautiful plant, even when it has lots of leaves. So is the use of extra fertiliser worth the trouble and expense? Keeping it simple - What about trying a simple hydroponic method of growing tomatoes? Can you get reasonable yields and does it have any effect on problems such as BER?
Home	No doubt the experts among you will feel that you know the answers to these questions. The inexpert will possibly have found it all too complicated to even care. However a lot of gardeners try to grow tomatoes - so, instead of trotting out all the traditional expert recommendations (which may or may not work) we tested a few ideas and you can see the results. You can then make up your own mind whether any of the ideas tested have anything to offer. The trial started in May 2000 and carried through into September/October. Details of the trial