Star Ruby Grapefruit Tree

Star Ruby Grapefruit (Citrus x paradisi 'Star Ruby') carries the deepest red flesh of any grapefruit, in fruit that is almost seedless and sweeter than the old white varieties. Grafted trees settle at about 3m to 4m tall and 3m wide in a home garden, small enough for a suburban backyard. Scented white flowers in spring turn into fruit that hangs on the tree for months, so you pick as you need it.

Why you'll love it

• The best flesh colour in the group. Star Ruby is the deepest red of the grapefruits, and the flavour is noticeably sweeter and less bitter than a white grapefruit.
• Almost no seeds. A practical difference at the breakfast table, and the reason this variety displaced the older reds.
• Fruit that stores on the tree. Ripe fruit holds for months without dropping, so one tree gives a long picking season instead of a glut.
• Roots that stay out of trouble. Citrus roots are non invasive, so the tree can sit near paths, paving and services.

Where it works best

Feature planting in a small garden. At 3m to 4m it works as the single fruiting tree in a backyard. Allow 3m of clear space and keep it away from competing tree roots and lawn.

Pots and courtyards. A pot 600mm or wider with free draining citrus mix holds it to around 2m. Container trees need more consistent watering and feeding than trees in the ground.

Growing Star Ruby Grapefruit in Australia

Position and climate. Full sun all day, with shelter from strong wind. It suits tropical, subtropical, warm temperate and Mediterranean gardens. It takes light frost only, so in cold districts grow it in a pot against a warm north facing wall.

Soil. Free draining, slightly acidic soil is essential. Citrus will not tolerate wet feet, so on clay build a mound at least 300mm high and plant into it. Keep mulch clear of the trunk to avoid collar rot.

Water and feed. Deep water twice a week through the first two summers, then weekly in dry spells and consistently while fruit is swelling. Feed a citrus fertiliser three times a year, in late winter, midsummer and early autumn.

Pruning. Very little. Remove shoots below the graft, take out dead or crossing wood, and open the centre lightly after harvest. Heavy pruning costs you fruit.

What to expect when it arrives

This one is grown in a single size, a 2.4L pot. That is a young grafted tree with a clear trunk and a small head, and it is the size most citrus is planted from, because young trees establish faster and out crop a larger transplant within a few years.

Trees travel upright and are delivered Australia wide, with delivery from $29.95 and a minimum order of $300 before delivery. Expect a light first crop in two to three years and a proper harvest from year four. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• How to grow citrus in an Australian backyard
• Browse the full citrus range
• Compare other fruit trees for the home garden

Common questions

How long until it fruits?

A grafted tree usually sets a light first crop in two to three years, with a worthwhile harvest from year four. Removing the first season of flowers helps it build a frame instead of ripening fruit.

Can I grow it in a pot?

Yes, in a pot 600mm or wider with citrus mix. Potted trees hold at around 2m and crop well, but they dry out fast and need feeding more often than trees in the ground.

Will it handle frost?

Light frost only. Young trees are the vulnerable ones, so protect them for the first two winters. In hard frosting districts a movable pot is the realistic option.

Why is my fruit not sweet?

Grapefruit needs a long warm season to develop sugar, and it sweetens further the longer it hangs on the tree. Leave it until well after it colours, and expect a sharper fruit in cool temperate gardens.