When to Plant Grapefruit in Cairns, Tropical Guide
What this month normally looks like in Tropical
In October the Tropical zone normally runs 34°C by day and 23°C overnight, with about 53 mm of rain over 5 or 6 wet days. Averages 1991 to 2026, 37 postcodes, SILO.
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This Grapefruit guide is written for the Tropical zone, which takes in Cairns, Townsville and Darwin. Somewhere else? Your postcode picks the right one.
Not your zone? Brisbane Sydney Melbourne Canberra Alice Springs Perth
Also handy: will it frost this week? and what grows in shade.
- Planting window
- Oct to Dec
- Sun
- Full sun
- Soil pH
- 6.0–7.0
- Shop price
- $3.90/kg at one shop
Large citrus tree that needs warm conditions and ample space. Produces heavy crops of tart-sweet fruit that hang on the tree for months (natural storage). Needs more heat than most citrus to develop sweetness.
Published · By GardenBuddy.au
Planting dates, current conditions and prices on this page update daily.
Photo: Wikimedia Commons
Best Planting Window for Tropical
- Jan -
- Feb -
- Mar -
- Apr -
- May -
- Jun -
- Jul -
- Aug -
- Sep -
- Oct P
- Nov P
- Dec P
P = Planting window
Plant grafted trees on a mound as the wet opens. Ripe fruit can hang on the tree for a few months, and rinds often stay green when ripe in the tropics.
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How to Grow Grapefruit in Tropical Australia
- Soil
- Well-drained, slightly acidic to neutral. Avoid heavy waterlogged clay. Sandy loam ideal. All citrus hate wet feet.
- Salt
- Sensitive. Struggles with salty bore water or salty soil. Give it rainwater if you can.
- pH Range
- 6.0-7.0
- Sunlight
- Full sun, minimum 8 hours. More sun = sweeter fruit. North-facing position ideal.
- Good companions
- Nasturtium, Marigold, Comfrey
- Keep away from
- Grass to trunk (competition)
Tropical Growing Tips for Grapefruit
Recommended Varieties
- Marsh (seedless white)
- Ruby Red (pink)
- Star Ruby (deep red)
Key Challenges
- Thick rind, less flavour development than in temperate zones
- Citrus leafminer year-round
- High disease pressure
Pro Tips
- Grapefruit grows vigorously in tropics but fruit quality is often mediocre. Lacks the heat/cool cycle that develops sweetness.
- Better citrus choices exist for tropics (limes, mandarins).
Pests and problems for Grapefruit in Tropical
Harvesting Grapefruit
When ready: Skin turns yellow (white varieties) or develops pink blush (red varieties). Fruit feels heavy for size. Taste test is the best indicator. Grapefruit sweetens the longer it stays on tree (can hang 6+ months).
How to harvest: Cut with secateurs or twist-pull. Don't tear bark. Harvest in dry weather.
Storing and preserving grapefruit
How to keep it
- Dehydrated slices. Slice 3-4mm thin. Dehydrate at 55°C for 10-14 hours. Use in drinks, cooking, decoration. Keeps: 12 months.
- Marmalade. Slice fruit including peel. Soak overnight. Cook with sugar (1:1 by weight) to setting point. Jar hot. Keeps: 12 months.
- Juicing. Juice and freeze in ice cube trays, then bag. Or pasteurise at 72°C for bottling. Keeps: 12 months frozen.
- Candied peel. Boil peel strips 3 times (changing water) to remove bitterness. Simmer in sugar syrup until translucent. Dry on rack. Keeps: 3 months.
What grapefruit costs in the shops right now, retailer by retailer, updated daily.
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- Soil and weather from your nearest station
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- Price history and price alerts
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- Full salt and canning detail
Common Questions About Grapefruit
When do you plant grapefruit in Australia?
It depends on your climate zone, not the calendar month alone. Planting months by zone:
- Tropical (Cairns): Oct to Dec
- Subtropical (Brisbane): Sep to Nov
- Warm Temperate (Sydney): Mar to Apr, Sep to Nov
- Cool Temperate (Melbourne): Oct to Nov
- Cold / Highland (Canberra): not recommended
- Arid / Semi-Arid (Alice Springs): Mar to Apr, Sep to Oct
- Mediterranean (Perth): Apr to May, Sep to Nov
When should I plant Grapefruit in Cairns?
Plant grafted trees on a mound as the wet opens. Ripe fruit can hang on the tree for a few months, and rinds often stay green when ripe in the tropics.
How do I know when Grapefruit are ready to harvest?
Skin turns yellow (white varieties) or develops pink blush (red varieties). Fruit feels heavy for size. Taste test is the best indicator. Grapefruit sweetens the longer it stays on tree (can hang 6+ months).
What are the best Grapefruit varieties for Cairns?
Recommended varieties for the Tropical zone include: Marsh (seedless white), Ruby Red (pink), Star Ruby (deep red).
What grows well with Grapefruit?
Good companion plants for Grapefruit include: Nasturtium, Marigold, Comfrey.
Are grapefruit salt tolerant?
No. Grapefruit are salt-sensitive, one of the more sensitive veggies. Use rainwater if your bore water is salty, or grow them in a raised bed of fresh mix if your soil is.
Which zone am I in?
Type your postcode into the box near the top of the page and it tells you, and links this crop in your own zone if it differs. Or look it up on the grow zone map. This page is the Tropical zone, Cairns is its reference city.