Disease Resistant Cultivars
Preventing garden disease
The first step to a disease free garden is the use of sound cultural practices. This includes:
- Crop rotation – rotating crop families through the garden beds
- Building healthy soil rich in organic matter (adding organic plant food through the growing season).
- Watering regularly and deeply (at soil level) – Avoid wetting foliage
- Mulching to protect foliage from soil borne diseases splashing onto foliage during wet weather
- Disposing of diseased plants outside of your garden system i.e do not compost diseased plant materials
- Maintaining good airflow around plants i.e. don’t overcrowd plants and stake or provide support for sprawling crops e.g. tomatoes and cucumbers
- Planting disease resistant cultivars. (see specific cultivar information below)
Disease resistant cultivars
Bush beans are also known by the names: Dwarf, French and Snap Bean. Climbing beans take up little room but are high yielding and nutritious. They bear later but longer than bush beans, ensuring a continuous supply. Beans grow well in all soils if not waterlogged and does best in near neutral pH soil. They can be frozen.
Cultivars grown/issues: Blue Lake (2012-2015). Develops rust every time they are grown even when rotated.
Bush Bean ‘Italian Romano’
A stringless bean with flat, medium-green pods 15 cm long with a meaty texture and excellent flavour. Beans hold well on the plant without becoming tough. Very disease resistant and productive. Days to harvest: 53 – 58.
Bush Bean ‘Jade’
‘Jade’ is a bush bean, producing dark green, tender, very straight, stringless, round pods, 15 – 17 cm long with a rich flavour. Highly productive with a long season. Days to harvest: 60.
Resistant to Common Bean Mosaic virus, Bean mosaic virus (strain 15), Curly top virus, cold, stress, rust and heat.
Bush Bean ‘Provider’
‘Provider’ is a bush bean, disease resistant and very productive. It has an upright growth habit; producing straight, tender, stringless, round pods, 17 cm long. This variety has the ability to germinate in cool soil so is a good choice for early spring sowing. Days to harvest: 50.
Resistant to Common bean mosaic virus, Bean mosaic virus (strain 15), Downy mildew, Powdery mildew, Pod mottle virus and cold.
Bush Bean ‘Roc D’Or’
‘Roc D’Or’ is a classic ‘French’ bean with crisp, golden yellow, slender, straight pods, 14 – 15 cm long, with black seeds and purple flowers. Excellent yields with good disease resistance. Germinates well in cool soil so is a good choice for early spring sowing. Days to harvest: 55 – 60
Bush Bean ‘Royal Burgundy’
‘Royal Burgundy’ is an open-pollinated bush bean, producing beautiful glossy, tender, stringless, round pods, 15 cm long. The delicious, violet-purple beans turn green when cooked. It is disease resistant and productive. Days to harvest: 52.
My notes: Purple colour may make harvesting easier.
Bush Bean ‘Simba’
‘Simba’ is an open-pollinated, smooth, round, stringless variety; producing very dark green, fleshy beans 13-14 cm long with a great flavour. It is a heavy cropper. A major commercial variety, very suitable for farmer’s markets. Days to harvest: 45 – 52.
Resistant to Rust, Summer Death and Halo Blight.
Very flesh, dark green, curved bumpy pods to 20cm. Small string if over mature, vigorous growing and good disease tolerance, large water requirements. Developed in W.A. 65 days.
Cultivars grown/issues: Nandes, Danvers, Yates Baby carrots (no diseases for all cultivars).
Carrots ‘All seasons’
Main Queensland variety, also popular in NSW. Virus resistant roots to 20cm. 65-80 days.
Sweet Corn ‘Bicolor’
Large cobs of supersweet corn, with an attractive colour contrast of cream and gold kernels; produces 2 cobs per plant, disease resistant. This is untreated hybrid seed with a high germination.
Sweet Corn ‘Max’
‘Max’ produces large cobs of golden corn on a hardy plant. A ‘supersweet’ (Sh2) supermarket hybrid, it contains about twice the amount of sugar of older varieties. It is also slower to convert sugar to starch, so retains its sweetness longer. It should be grown at a different time to other sweet corn as cross-pollination will reduce its sweetness. High germination.
Height of plant: 196 cm. Days to harvest: 85. Resistant to Rust.
Cultivars grown/issues: Marketmore (2012-2016). Extremely productive with few disease issues.
Cucumber ‘Marketmore’ * ‘Marketmore’ produces attractive, non-bitter, dark green fruit 20 cm long. It has good disease resistance and is highly productive. Days to harvest: 60 – 70.
Cucumber ‘Giant Russian’
Excellent variety for humid areas, vigorous vine, fruits are very large, crisp, sweet and acid-free, keep for several months.
Much more resistant to mildew than Lebanese cucumbers.
Cucumber ‘Green Gem’
Long slicing type, to 25cm long. Does well in hot climates with heavy yields. Days to harvest: 56-63.
Resistance to mildews.
Cucumber ‘Gympie Gold’
‘Gympie Gold’ has large, golden yellow, oblong fruit with low acidity. It stays sweet and crisp even when older and stores well in the fridge. It has good disease resistance and is very productive. It is best picked around 16cm long when still pale lemon-green; mature size is 25cm long with a diameter of 12cm. Days to harvest: 65.
Apple type, 80-55mm, ripens to light yellow, bitterness free, heavy producer. Days to harvest: 58-70.
Resistant to Rust and drought.
Cucumber ‘Muncher Burpless’
Tender burpless slicing variety. Can be used in pickles also. 17cm long smooth bitterness free green skin. Days to harvest: 65. Resistant to Mosaic Virus.
‘Spacemaster’ is a very productive, bush variety, 90 cm across; suitable for growing in containers or by market gardeners. Fruit is slender, dark green, 17 – 22 cm long with a crisp, sweet flavour. It is disease resistant. Good for salads or pickles, if picked young.
Climbing peas yield more peas over a longer period that bush/dwarf peas. Keeps well in fridge for weeks. Can be frozen. Peas dislike acidity, so lime if necessary.
Cultivars grown/issues: Greenfeast is my usual shelling/English variety. Still gets powdery mildew though even though its technically resistant.
Pea ‘Greenfeast’ *
Greenfeast syn. Lincoln is a heavy bearing bush shelling pea to 1m, hardy and disease resistant. It is good for home gardeners as it harvests over a longer period. Days to harvest: 65 – 70.
Snowpea ‘Oregon Sugar’
Snowpea bush type to 70cm, that is disease resistant and heavy cropping. Pods are 11 cm long, crisp, tender, full of flavour and great in stirfries. Days to harvest: 60 – 70.
Snowpea ‘Oregon Giant’
Large dark green pods, plant to 1 metre tall. Resistant to Powdery Mildew with some Root Rot resistance also.
Pea Sugarsnap ‘Cascadia’ +
A climbing pea to 110 cm, with thick, juicy, edible pale-green pods, 6 – 7 cm long; sweet and flavourful. It is very productive. Days to harvest: 58 – 65. Resistant to Powdery Mildew.
Cultivars grown/issues: French Charentais (2013-2015)Gets Powdery mildew and suspected Downy mildew. Sprays of potassium bicarbonate damage foliage.
Rockmelon ‘French Charentais’
Delicious fragrant and juicy. The best tasting rockmelon I have eaten.
My notes: This is the only variety I have grown. Although it is meant to be resistant, it still gets Powdery Mildew (and suspected downy mildew) every year. Treatment with Eco fungicide burns leaves.
Rockmelon ‘Hales Best’ +
An early rockmelon that has large (2 Kg) fruit with a rich aroma, orange flesh and a lovely classic melon taste. It tolerates wet conditions and performs extremely well in drought. Fruit grows up to 20 cm in diameter. They have a moderately sized seed cavity and good sugar content. Days to harvest: 85-90. Available from The Lost Seed.
Resistant to Powdery Mildew, drought and rot.
Hearts of Gold (aka Hoodoo) Resistant to Blight
Minnesota Midget Resistant to Fusarium wilt
Cultivars grown/issues: Tigerella, Broad Ripple Yellow Currant (2012-1015), Yellow Pear, Powdery mildew, Blight.
Mighty red (slicing tomato) F1 hybrid indeterminate, 3.5 metres tall, fruits: 8.5cm diametre, sets fruit in the heat, massive trusses, tastes similar to Grose Lisse Disease resistance: Root Knot Nematode, Verticillium Wilt, Fusarium Wilt, Tomato leaf Mosiac Virus Available from Bunnings as a grafted plant.
Bite Size (cherry tomato) F1 hybrid indeterminate, 2.2-2.7 metres tall, train to 3 leaders, fruit 3cm in diametre, matures in 77-84 days (from seed) Disease resistance:Verticillium Wilt, Fusarium Wilt, Bacterical Speck and Late Blight.
Tomato Cherry ‘Broad Ripple Yellow Currant’ *
Masses of sweet acidic yellow fruit to 10mm. grape like bunches. Doesn’t split when left on vine. Survives harsh conditions and resows itself.
Pest and disease resistance: Fruit fly resistant. Gets powdery mildew in wet conditions but still keeps producing.
My notes: Proven an excellent producer over a long period with little effort.
Tomato ‘Rouge de Marmande’ syn. ‘Early Girl’ +
A French heirloom that produces clusters of 170g deep red, slightly flattened, ribbed fruits that are up to 9 cm across. The fruit has an outstanding flavour and very few seeds. It will set fruit well in cooler conditions than other varieties. Good disease and pest resistance. Days to harvest: 65 – 75.
My notes: One to try for next year. Handles disease well in Sydney. See this forum post
Tomato Cherry ‘Camp Joy’ syn. ‘Chadwick Cherry’
An heirloom with fruit a little larger, 3.5 cm, than other cherry types, carried in clusters of 6. It has a delicious, sweet flavour and is very productive and disease resistant. ‘Camp Joy’ is an indeterminate type so requires staking. Days to harvest: 80.
Tomato Cherry ‘Cocktail’
A bright red cherry tomato, exceptionally sweet, very prolific with large trusses of fruit ripening at the same time on vigorous plants. Ideal for salads, early maturing and disease resistant. It has a semi-determinate plant habit; staking is recommended.
Tomato Cherry ‘Tommy Toe’
Medium sized red fruit 20-40mm, cherry shaped, tasty and long cropping, needs staking. Disease resistant.
Tomato Cherry ‘Yellow Honey Bee’
A bright yellow cherry tomato, exceptionally sweet, very prolific with dozens of little, 2.5 cm fruit in clusters. It is early maturing and disease resistant. It has a semi-determinate plant habit; staking is recommended. Excellent for salads. Days to harvest: 55 – 68.
Tomato ‘Kotlas’ syn. Sprint
Extra early, medium sized, round, tasty red fruit, cold tolerant, great tasting, Determinate. Long season due to blight resistance. Days to harvest: 60. Resistance to Blight.
‘Scorpio’ is an Australian variety suitable for sub-tropical conditions. It produces smooth, red, medium-sized, round fruit. Indeterminate type so requires staking. The fruit has solid flesh with a good flavour. Days to harvest: 69 – 80. Resistant to Bacterial Wilt and copes with humidity
Tomato ‘Thai Pink Egg’
Delicious, sweet, pink, grape-shaped, 40 mm long fruit are sold in Thai markets. A very heavy cropper. Days to harvest: 60 – 65. Resistant to cracking even in heavy rain.
Deep red large round fruit to 9cm. Disease and crack resistant. Days to harvest: 68.
Black Russian appears to be the standout Heritage variety for taste (not specifically for disease resistance)
Cultivars grown/issues: Blacktail Mountain 2013, 2014. Surcomes to unknown disease (possibly Sudden Wilt).
Watermelon ‘Charleston Grey’ syn. Candy red +
Flesh is bright red, crisp and sweet. Large oblong fruit to 15kg. Light green skin with dark green stripes. Early producing. Days to harvest: 85-100. Available from Green Harvest. Resistance to Anthracnose, Fusarium Fruit rot, Fusarium Wilt (race 0) and sunburn.
My notes: Trying this one next. If not available try Crimson Sweet.
A large, oblong melon with striped green rind and sweet red flesh. It is disease resistant with few seeds and keeps well.
Watermelon ‘Crimson Sweet’ syn. Warpaint
Fruit is round, dark green with large stripes, 10-12 kg with bright red, very sweet, juicy flesh with a fine texture. Days to harvest: 80-97.
Resistance to Anthracnose, Fusarium Fruit rot and Fusarium Wilt (race 1& 2).
Available from: Yates & Green Harvest
Watermelon ‘Country Sweet’
A high yielding, disease tolerant fruit is favoured for its vivid red, sweet, juicy flesh.
Available from Yates.
Biggest issue: Powdery mildew
I have found it difficult to find green fruiting varieties that are truly resistant to powdery mildew. Yellow fruiting varieties offer better resistance but I’ve found they are not as productive. As such, I’ve paid particular attention to maintaining good cultural practices along with applying organic sprays at first sight of disease.
Remove older leaves to improve airflow, leaves affected by disease. Treat with weekly bicarbonate soda or potassium bicarbonate sprays to keep the disease from spreading and to maintain productivity.
My favourite: Black Beauty – Very productive. Use tips above to manage powdery mildew.
- Zucchini variety disease resistance table
- Identification and management of Cucurbit diseases
(Includes watermelons, cantaloupes, cucumbers, zucchini, pumpkins, squash, bitter melons, gourds, and hairy melons).
Terminology & Guide
- Disease resistant – Less likely to get disease specified.
- Disease tolerant – Cultivar may get disease but should remain more productive than non tolerant cultivars.
- * Productive variety – will grow again
- + Promising variety to try
Identification and management of Cucurbit diseases
Cucurbits include watermelons, cantaloupes, cucumbers, zucchini, pumpkins, squash, bitter melons, gourds, and hairy melons.