Tomato Talk & Terminology
The most common diseases of tomatoes include:
Early and late blight: Both Fungal diseases causing leaf spots and yellowing. Difficult to treat but can be prevented using the strategies listed below.
Fusarium and Verticillium Wilt: Fungal disease present in soil. Remove all plant matter – do not compost
Septoria Leaf Spot: Fungal disease. Leaves first appear with brown spots then colouring to yellow.
Heirloom tomato varieties are more susceptible to disease. Tips for reducing disease outbreaks and recurrences include:
- Choose disease resistant cultivars.
- Water soil or under mulch and avoid wetting foliage.
- Never in the evening to allow wet leaves to dry quickly.
- Avoid overcrowding plants and ensure good air circulation with good spacing and staking.
- Practice crop rotation to prevent disease build up in the soil.
- Do not compost diseased plants by bag them up and place out with the rubbish or burn, don not compost.
- Keep beds weed free.
Cracks: a characteristic of a tomato variety that inherently resists breaks in its skin. Cracks are usually caused by inconsistent or excessive irrigation or rain. Some tomato varieties are more crack resistant than others.
Blossom end rot: Causes the appearance of a water soaked spot at the flower end (bottom of the tomato) and is causes the fruit to rot. Blossom end rot is caused by calcium deficiency. Keep soil evenl moist throughout the season and do not overfeed with high nitrogen fertilisers such as chicken manure.
Physiological leaf curl: Usually the result of heat stress. Keep well watered in hot dry conditions.
Mediterranean & Queensland Fruit Fly lay eggs in fruit, resulting in white maggots found in ripened fruit and causing fruit to rot. Monitor fruit fly presence with fruit fly traps. Once detected, cover crops with fine netting or enclose individual bunches of fruit in exclusion bags. Cherry tomato varieties are less susceptible. More QFF information.
Snails and Slugs: Chew large holes in fruit. Train plant so leaves don’t come in contact with the soil. Use iron-based snail pellets. Coffee grounds may deter them. Snail and slug management.
Caterpillars chew holes in leaves and enter fruit when very small feasting on the insides and cause the fruit to rot. Spray plants with Bacillus thuringiensis (Dipel) or cover crops with fine netting to keep adult moths from laying eggs on plant material.
Tomato types & productivity
Determinates & Indeterminates
Determinate/Indeterminate/Semi-determinate: a term used to classify tomatoes based on the length of time the plant produces fruit during the season.
Determinate tomatoes produce for a couple of weeks only then production slows.
Indeterminate tomatoes produce fruit over a much longer period and will continue to produce fruit throughout the season until the plant dies back naturally at the end of the season. They are generally much taller than determinate tomatoes with some cultivars reaching 3 or 4 metres tall and therefore require strong trellising.
Semi-determinates are short-vined tomato plants. Semi-determinates continue to grow and produce longer than determinates, but plants don’t get as large as indeterminates.
Days to maturity: the number of days from transplanting a seedling into the garden until its first mature fruit. Early season varieties mature in 55 to 68 days; midseason varieties in 69 to 79 days; late season varieties in 80 days or more.
Heirloom vs hybrid tomatoes
Heirlooms: Old tomato varieties that have been around for many generations without cross-breeding.
Hybrids: Tomato varieties that have been cross-bred between two different varieties to produce an ‘improved’ cultivar.
- F1 hybrid: the first generation seeds that come from plants with two specific parents
- F2 hybrid: seeds that come from crossing two F1 hybrid parents
Open-pollinated (OP): A tomato variety that has been pollinated by its own variety. All heirloom varieties are open-pollinated. Not all open-pollinated varieties are heirloom varieties.
Extract from TomatoDirt.com