WHEN TO PLANT: Sow seeds under cover August to September. Plant out / pot up October to November. Frost sensitive!
WHERE TO GROW: In Otago, tomatoes are usually grown in glass/tunnel houses, conservatories and windowsills. They like a lot of sun and warmth and shelter from wind. Tomatoes are known to not do that well outdoors in Dunedin, but you have a good sunny, sheltered area, then you've got a shot at a good yield. Success has been had with 'Roma', 'Siberian' and 'Russian Red' and 'Oregon Spring' varieties outdoors, in well composted, straw mulched soil.
'Determinate' tomatoes produce a single 'flush' of fruits, which can be bountiful, but then they are more or less finished. 'Indeterminate' tomatoes grow until frost stops growth, producing a more steady stream of fruits. It is important to train these to provide them with support - one way is to bury a string under the plant that you then attach to a structure above. As the plant grows wind the string up the vine being careful to go above the fruit truss, remember to pinch out all the laterals which encourages fruiting rather than just leaf growth.
SOIL REQUIREMENTS: Tomatoes like a fairly rich soil which a medium tilth. A large portion of their mix can be well matured compost. Drainage is important too. Tomato plants need quite a bit of water, but they can't handle having 'wet feet'. As such, a soil with a good humus content that holds water but allows for air spaces is desirable.
PLANT SPACING: Depending on variety, but generally for indeterminate tomatoes around 60 cm and a bit more for bush varieties.
WATER and FERTILISER: It is important to water in the morning, to prevent chill at night. I give one good soak a week which helps to encourage good, deep, root growth.
To encourage further flowering it is a good idea to give a liquid feed of fish and comfrey.
HARVEST and USE: Harvest tomatoes when they are well ripe. That is the joy of growing your own, you don't have to put up with these hard, flavourless things from the supermarket. Use fresh tomatoes however you desire. Tomatoes are also great turned into a paste or they can be canned. In Otago, often peoples tomato crops do not fully ripen. As such, green tomato relish/chutney is popular, and it is delicious.
SEED SAVING: Tomatoes are self pollinating - they do not cross with other tomatoes without human intervention.
To save seed from your tomatoes, remove the pulp from a few fully ripe (or even over ripe) tomatoes from plants that have preformed well (i.e. early fruiting, good taste, prolific harvest, etc). Place the pulp in a clean drinking glass or jam jar on your kitchen windowsill, covered with a tea towel or similar. Allow the mash to ferment for a few days.
After three days or so, a layer of 'tomato mold' will form on the top, and the seeds settle to the bottom of the liquid. Slowly run water into the glass to float off the pulp, leaving the seeds. Pour seeds into a strainer, wash them thoroughly in cold water, and dry them on a sheet of paper or a tea saucer. This fermentation process is critical in yielding good quality viable tomato seeds. It also makes removing the pulp from the seeds much easier. Don't worry too much if some paper sticks to the seeds, they will germinate anyway.
CHILLIES and PEPPERS
WHEN TO PLANT: Plant seeds in trays/punnets September - October. Pot up seedlings October - November. FROST SENSITIVE!
WHERE TO GROW: The same notes apply for peppers and chillies as for tomatoes. Glasshouse type conditions are preferred for optimal yields. Peppers and chillies are more cold sensitive than tomatoes. If growing outdoors, a shelter can be made from old windows, or a makeshift mini greenhouse should be constructed for them.
SOIL REQUIREMENTS: See tomatoes
PLANT SPACING: Space chillies about 30-50cm apart. If growing in pots, 15 litres is a good minimum size to aim for, with closer to 30 litres being ideal.
SEED SAVING: Unlike tomatoes, peppers and chillies DO cross pollinate one another. As such, if you aim to collect seed, they should be kept in separate areas. In particular, hot chillies and sweet peppers need to be kept separate, or else you could end up with hot peppers or sweet chillies, which can get a little unpredictable! Could be fun though...