Leslie Massey
Growing tomatoes in Australia can be challenging due to the varying climate zones and common issues with pests and diseases. From fungal infections like blight and powdery mildew to pests such as aphids and thrips, Australian tomato growers must be vigilant in caring for their plants. This is particularly true in humid or rainy weather, when fungal diseases can thrive, and in regions with specific climate conditions, like the coastal areas of south-eastern Australia. Proper spacing, airflow, and soil management are crucial to preventing problems. Additionally, pest control methods like insect exclusion bags and sprays can help protect tomato plants from destructive insects, nematodes, and mites.
| Characteristics | Values |
|---|---|
| Insects | Aphids, Thrips, Fruit flies, Mites, Budworms, Slugs |
| Diseases | Blight, Powdery Mildew, Leaf Spot, Downy Mildew, Rust, Fusarium Wilt, Bacterial Wilt |
| Symptoms | Brown/black patches, holes, chewed edges, fuzzy mould, yellowing leaves, wilting, stunted growth, purpling leaves, scorching, chlorosis |
| Causes | Poor cultivation, bacteria, fungi, calcium deficiency, temperature fluctuations, overwatering, high nitrogen levels, low humidity |
| Solutions | Pruning, fungicide, pest control, soil testing, calcium supplements, mulching, fertiliser, staking, shade, spacing, foliar spray |
Explore related products
Insects, nematodes, and mites
To prevent pest damage, you can spray your plants with a splash bait containing spinosad once a week to reduce pest numbers. You can also place insect exclusion bags or sleeves, made from waxed paper or insect netting, over the green fruits.
Aphids are small, soft-bodied insects with thin legs that are usually green, grey, or black in colour. They are most commonly seen in spring and autumn when the weather is mild and humid. They can lead to serious virus infections in tomato plants, so it is important to control their populations. Yates Tomato Dust and insecticidal soap can be used to control sap-sucking insects like aphids and thrips.
Other common pests include the Australian native blue-banded bee, which is a special insect that pollinates tomato flowers. However, if you notice any insects on your plants that you cannot identify, take a photo and contact your local Cooperative Extension agent for help. They will be able to provide you with information on how to manage the pest.
Amber Discovery in Australia: Where and How?
You may want to see also
Explore related products
Calcium deficiency
Another issue associated with calcium deficiency is the presence of pests and diseases. Tomato plants are susceptible to damage from various insects, nematodes, and mite pests, such as the Queensland fruit fly and the Mediterranean fruit fly. These pests can attack the leaves and fruit of tomato plants, leading to spotting, wilting, and destruction of the plant. To control pest numbers, it is recommended to spray with a splash bait containing spinosad weekly. Insect exclusion bags or sleeves made from waxed paper or insect netting can also be placed over the fruit.
Additionally, calcium deficiency can make tomato plants more vulnerable to diseases such as fusarium wilt, which is characterised by yellowing of the lower leaves, followed by browning and wilting. To confirm the presence of fusarium, one can split open the stems; if they reveal pink to brown discolouration, the disease is present. Maintaining a pH of 6.5–6.8 can create an unfavourable environment for fusarium.
To prevent calcium deficiency in tomato plants, it is essential to ensure proper soil nutrition. Before planting, conducting a soil test with a local garden centre or cooperative extension is advisable, as they can provide recommendations for adjusting the soil composition. Calcium can be added to the soil through the addition of lime and gypsum, but these must be added in the proper amounts based on the soil's condition. Incorporating crushed eggshells into the compost pile is another effective way to boost calcium levels naturally when compost is added to the soil.
Biggest Loser Australia: What's on the Menu?
You may want to see also
Explore related products
Sunscald
The symptoms of sunscald on tomato leaves include gray-white blotches appearing on the leaves in hot and sunny weather. This is essentially a form of sunburn, and it can cause discolouration and damage to the leaves. The leaves may appear similar to human skin after exposure to the sun, with a sudden burst of sunlight causing the discolouration.
To prevent sunscald on your tomato plants, it is important to provide adequate shade during the hottest parts of the day. This can be achieved by leaving some foliage and branches on the plant to provide natural shade. Additionally, you can use tomato cages or a wire support system to surround the plants, providing additional shade and support.
If your tomato plants do develop sunscald, it is important to know that they will likely recover. The affected leaves may die, but the plant should regenerate new, more resilient leaves. You can also help the plant recover by providing some shade during the day, such as by placing something in your garden to block direct sunlight during certain times.
Koala Culinary Confusion: Australian Appetite for an Iconic Animal
You may want to see also
Explore related products
Soil pH
If the soil pH is too high or too low, certain nutrients can become unavailable to the plant. For example, phosphorus is unavailable to tomatoes when the pH is outside of their preferred range. Tomatoes also need a decent amount of calcium to avoid blossom end rot disease, and if the pH is too low, they may not be able to absorb enough calcium from the soil.
You can check the pH of your soil with a testing kit, which can be purchased online or from a garden centre, or by sending a sample to a laboratory for testing. If your soil pH is above 6.7, it is alkaline, and if it is below 6.2, it is too acidic for your tomatoes.
To raise the pH of your soil, you can add lime, which also provides calcium and magnesium, two important elements for plant growth and health. Dolomite lime is a common additive for this purpose. If your soil is particularly alkaline, you can add powdered sulphur to lower the pH over time.
Lowering the pH of your soil is fairly straightforward but will take time. You can add plenty of compost or other organic matter to the soil to lower the pH. However, it is recommended that you do not use poultry manure for this purpose, as it has a pH range of 6.5 to 8, which is more alkaline. Similarly, mushroom compost should be avoided as it tends to have a pH range of 6.5 to 8.
Kangaroo Meat: A Staple in Australian Diets?
You may want to see also
Explore related products
Powdery mildew
The disease is favoured by high humidity (85-100%) and temperatures of 15-27°C, although some sources state that it develops in the absence of rain and at temperatures above 20°C. It tends to diminish in spring as temperatures rise above 25°C and as humidity declines. Dry weather, high-humidity conditions, and temperatures between 15°C and 27°C favour disease development. The fungus survives on diseased ratoon crops via overwintering fruiting bodies (cleistothecia).
Management strategies for powdery mildew include the use of resistant plant varieties, controlling volunteer wheat, crop rotation to avoid stubble-borne infection, efficient use of seed dressings and foliar fungicides, and nitrogen management. It is important to monitor powdery mildew incidence regularly and remove infected fruit to minimise the spread of spores. Fungicides can be applied to affected plants, and it is recommended to check the Australian Pesticides and Veterinary Medicines Authority database for chemicals registered or approved to treat powdery mildew on the target crop in your location.
Eating Disorder: Seeking Help in Australia
You may want to see also
Frequently asked questions
There are several pests that could be responsible for eating your tomato leaves. These include:
- Aphids
- Thrips
- Queensland fruit flies
- Russet mites
- Budworms
- Slugs
If you are unsure, take a photo and contact your local Cooperative Extension agent to identify the insects.
To prevent pests from eating your tomato leaves, you can:
- Apply insecticidal soap, such as Yates Nature's Way Vegie & Herb Spray, to control sap-sucking insects like Aphids and Thrips.
- Spray with a splash bait containing spinosad weekly to reduce pest numbers.
- Place insect exclusion bags or sleeves, which are made from waxed paper or insect netting, over the green fruits.
- Train plants so that leaves don't come into contact with the soil.
- Use slug traps and pet-safe baits.
If you notice any of the following symptoms, it is likely that your plant is affected by a disease:
- Brown or black patches on leaves
- Yellowing on the bottom leaves that work their way up the vine
- Light and dark green blotches on the leaves and sunken brown patches under the fruit skin
- Hollow fruit
- Distorted leaves with dark brown to black spots with concentric circles
- White or grey powdery patches on leaves
