Yes they are technically a fruit, but so commonly a part of our vegetable gardens that I have put them into this section.
Probably the most popular of all the home grown vegetables. The tomato (Lycopersicum esculentum) is a member of the Solanaceae family (Nightshade family), which also contains capsicum, chillies, eggplants, and potatoes. Tomatoes are definitely a crop that first time growers should try, and you will be so impressed with the difference in flavour compared to the supermarket supplies. Home grown tomatoes that are allowed to ripen on the plants have a sweeter and stronger flavour.
The cherry tomato varieties are great for kids – I remember when our 3 year old didn’t like tomatoes, that changed very quickly when the cherry tomatoes started to fruit – he would just stand near the vegetable garden and eat them straight off the bush!
Site and Soil Preparation
As with most vegies, your site will need to have adequate light – so a north facing position is ideal. Ideally plant where a building or wall could provide some shade in the late afternoon.
Tomatoes take about 3 months to grow and fruit, and need a warm climate. The soil should be free draining and contain sufficient organic matter to assist with structure and initial nutrient needs.
Seeds or Seedlings?
Raise seedlings yourself, or purchase as single plants or in punnets from a garden centre. I prefer to raise from seed, often retaining seed from an enjoyable variety grown the previous year (this only works with open/heirloom varieties).
Don’t be tempted to rush them into the ground at the start of spring, as the soil temperature can still be quite cold and there may be some chilly nights still to come. Better to pot them up into 20cm pots, and keep them in a cold frame or glasshouse until the garden bed is ready. Those lucky gardeners living in warmer areas up north can grow tomatoes pretty much year round.
Selecting the variety of Tomato
Selecting the variety of Tomato is something you can experiment with each year. In Australia you will always find the tried and tested top performing home garden varieties such as “mighty Red” and “Grosse Lisse”.
Popular tomato varieties in Australia include “Grosse Lisse”; “Roma”; and “Mighty Red”. I really like the heirloom varieties, particularly different colours like “Green Zebra” and “Black Russian” look just beautiful sliced into a salad.
Determinate or indeterminate varieties refer to the growth habit of the plants or vines.
Adding fertiliser is a good idea throughout their growing season, they are in particular need of phosphorous to set flowers for fruit – so be careful not to be too heavy with nitrogen fertilisers that lack sufficient potash.
Adjusting soil pH prior to planting can also be a good idea to assist in the prevention of blossom end rot, a pH of around 6.5 is ideal.
Tomatoes will benefit from light shade during January and February, for which a 50% shade white shade cloth is ideal. It will allow enough light for growth, flowering and fruit set – but reduces temperatures and therefore heat stress, improving yields.
To prune or not to prune? (Information in this section on pruning derived from the article “Training Systems and Pruning in Organic Tomato Production” authors Bonnie Cox, Oregon Tilth)
By pruning you are seeking balance between vegetation growth and fruit production. Pruning will impact fruit size, fruit quality and yield, so it is important to strike the right balance between reducing vigorous foliage and stripping the plant. The risk is that pruning too heavily can reduce yield and increase problems with sunburn and blossom end rot.
In determining how to prune your tomato crop, consider the growth habit (determinate or indeterminate) of your plants. Indeterminate tomatoes are more heavily pruned than determinate ones, but even determinate tomatoes often require some level of pruning. Next, consider any special features of your specific variety including any recommendations from your seed supplier. The amount of pruning needed can vary with variety.
Pruning is usually started as the plants are first being staked or supported, sometimes before stringing them to avoid interference with the lines. Tomato plants are pruned by selectively removing suckers, the shoot that grows between the main stem and a leaf. Suckers should be broken off while they are still small, between 2-4 inches in length. Prune plants only when the leaves are dry to reduce the spread of disease.
Plants in the trellis system are generally trained to two stems: the main stem and the stem that develops from the sucker just below the first flower cluster. Suckers below this one should be removed. The remaining two stems should be twined around the vertical string support as the plant grows. If very vigorous plants grow above the top of the stake system, they may need to be topped.
See image below from Kemble, J.M., L.M. Curtis, and T.W. Tyson. 2000. Guide to commercial staked tomato production in Alabama [Online]. Auburn University Extension Publication ANR-1156.(Link to paper here)
Pests, Diseases and Nutritional Problems
Common Problems are detailed in the below table.
|Brown patches on fruit, may look papery or a bit scabby||Sunburn||Throw an old sheet over the tomatoes on extreme days. Use a 50% white shade cloth over the garden|
|Tiny white insects under the leaves – they fly off when disturbed||White fly||Difficult to manage, try using yellow sticky traps or a pyrethrum spray. Alternatively try a spinosad product like Yates Success.|
|Large holes in the leaves, stems and even the fruit||Caterpillars||Various types of caterpillar can be found in the garden. Try picking them off by hand (great job for the kids!), or use a spray to manage the population. I prefer a product like DIPEL or SUCCESS. A general tomato dust will also do the job.|
|yellowing, then brown and dried lower leaves. Fruit fails to ripen and is flavourless.||Tomato russett mite||The mites are teeny tiny and you can’t see them, even with a magnifying glass. Spinosad and sulphur form the best option – found in most Tomato Dust brands. Apply every 7-10 days for best results.|
Pick when red (assuming you are growing a red variety!) and use straight away, while fruit will ripen slightly when picked early – the best flavours develop on the plant. If you want to preserve tomatoes they need to go through a cooking process before bottling. Picked tomatoes should be stored at room temperature, try to avoid putting them in the fridge.
Cooking with Tomatoes
Best used fresh in salads or to make a bruschetta, tomatoes can also be cooked into fantastic pasta sauces and preserved into relishes.