HOW TO PRUNE TOMATO PLANTS
By David Marks
There seem to be few subjects which cause amateur gardeners as many problems as pruning tomato plants. In reality though it's not that complicated if you are armed with two key pieces of information:
- Is the variety you are pruning a cordon or bush type? Our list of variety names below will sort that out for you.
- When tomato plants have developed fruits about the size of a small marble they can grow to maturity with very few leaves – far fewer than you might believe. This snippet of information will give you confidence when thinning out foliage.
CORDON AND BUSH TOMATO VARIETIES
Below we list the most common tomato varieties and classify them as cordon or bush types. Note that bush types are sometimes also called determinate; cordon types are sometimes also called indeterminate or vine. Bush tomato types are pre-programmed in their genes to produce a plant of a certain shape, size and with a pre-determined number of stems and side-shoots. In general, "nature knows best" so these tomato types can largely (but not completely) be left to their devices. The will need help in removing some lower down foliage and thinning out of their leaves, the reason being that tomato plants are sub-tropical in nature and you, in all probability, are trying to grow them in the temperate UK!
Cordon tomato types are not genetically pre-programmed as far as size is concerned and therefore need to be pruned to a specific shape when grown in the UK.
For other tomato varieties which we have fully reviewed, click the drop down box below, select a variety and then click the More Information Button.
POPULAR CORDON TYPE TOMATO VARIETIES
Abraham Lincoln, Ailsa Craig,Alicante, Amish Paste, Amy's Sugar Gem, Berry, Black Cherry, Black Krim,Black Russian, Blizzard, Brandywine, Brutus, Cherrola, Chocolate Cherry, Cossack, Country Taste, Craigella, Cristal, Crimson Crush, Cuore di Bue, Ferline, Fireworks, Flamingo, Gardeners Delight, Ghost Cherry, Golden Cherry, Golden Sunrise, Herald, Katiebell, Lizziebell, Lldi, Lucciola, Luciebell, Mexico Midget, Moneymaker, Orange Paruche, Orkado, Outdoor Girl, Pintyno, Rosada, Sakura, San Marzano, Santonio, Satyna, Shirley, Stupice, Sun Baby, Suncherry Premium, Sungold, Sungrape, Sweet Aperitif, Sweet Baby, Sweet Million, Tamina, Tigerella, Yellow Perfection, Yellow Stuffer, Zlatava
POPULAR BUSH TYPE TOMATO VARIETIES
POPULAR SEMI-BUSH TOMATO VARIETIES
Glacier, Losetto, Roma VF, Super Marmande
REMOVE DEAD OR YELLOWING TOMATO PLANT LEAVES
Some time around the end of June / early July you will have a strong growing tomato plant and in all likelihood you will be able to see small tomato fruits which have formed. For both cordon and bush types, remove any foliage lower down the plant which is touching the ground or nearly touching it. This will hep prevent diseases which can be splashed onto the plant by raindrops hitting the ground. In most cases young stems and leaves can be removed by bending them back until they snap off the main stem – this is the best way. Larger stems may need to be pruned away with a sharp pair of secateurs. Remove any yellowing or diseased looking leaves which will generally be on the lower half of the plant. Now take a look at the places on the plant where fruits are forming – remove any leaves which are covering the fruit. Tomatoes ripen quicker and benefit from exposure to the sun – too many leaves over the fruit can prevent this happening.
For the rest of the growing year perform the above two pruning / thinning exercises every week or two.
Cleanliness is key to preventing diseases on tomato plants, so as you prune stems and remove leaves be sure to pick up all leaves in the surrounding area and burn them.
Bush type tomato plants need minimal pruning because genetically they produce stems only where required. The pruning mentioned in the section above should be sufficient.
Cordon type tomato plants do require pruning in order to maximise the production of fruit and reduce the risks of moulds and other diseases.The picture below shows two key pruning points for a cordon tomato, click the picture if you want to enlarge it.
The basic principle behind pruning cordon type tomato plants is that you want the main stem (the one that emerges from the soil / compost) to be the one from which all the leaf stems emerge from. Take a close look at the picture above and see what's in the upper blue circle. The main stem is the largest one growing upwards, there is also a leaf stem which is growing at right angles to the main stem. In between them, in the picture it's referred to as "older growth remove", there is a new main stem forming and that should be pruned away. When you do this don't remove the nearby leaf stem and do not damage it.
Below in the picture there is another blue circle which shows a similar situation but the growth to prune away is at a much younger stage.
Both of the shoots in the picture above can be removed by bending them over with your fingers until they snap off. This is probably the easiest way to remove them and it also results in the least damage to the tomato plant. Examine the plant every week or two from top to bottom and remove all the new main steps as described above.
If you are growing cordon tomatoes for the first time we recommend pruning exactly as described above. If you are a little more adventurous you may want to try a variation on the above method which may, in some circumstances, results in a larger crop over a slightly longer period. The principle is to allow more than one main stem to grow, a good number would be three but definitely no more than four. Clearly, main stem 1 would be the one appearing from the soil, stem 2 would be from one of the lower shoots and stem 3 would be another shoot about 15cm / 6in above. Treat all three main stems as if they were the main stem as described above.
Having explained all the complexity of pruning cordon tomato plants correctly, every year my partner annoys me by doing absolutely no pruning to her Alicante tomato plants but producing masses of healthy tomatoes every time! Truly annoying!