Sacramento Digs Gardening logo
Sacramento Digs Gardening Article
Your resource for Sacramento-area gardening news, tips and events

Articles Recipe Index Keyword Index Calendar Twitter Facebook Instagram About Us Contact Us

Mystery fruit looks like fuzzy navels

Green citrus fruit hanging over a fence
Notice the three-part leaves on this citrus tree. They are a clue to its identity. (Photo courtesy Allen Pierleoni)

Citrus rootstock sprouts a trifoliate orange tree

“What’s growing over my fence?”

That’s a common question from many gardeners, one that I ask myself sometimes, too.

In the case of fruit, it comes with a corollary: “Can I eat it?”

Such is the case of this mystery fruit, spotted by a loyal reader in Fair Oaks. He pondered whether he was going to get some bonus citrus – or should cut the branches back.

“The skin is slightly velvety, the plant is growing next to a grapefruit tree. Unusual leaves, no?” he wrote in a note with his photo of what looked like fuzzy navels.

All three observations were clues to the mystery fruit’s identity – plus one more. Look out for those great big thorns.

The fruit is a trifoliate orange ( Citrus trifoliata ), also known as Japanese bitter orange or Chinese bitter orange. And it sprouted from the rootstock of the grapefruit tree.

Allowed to grow and thrive, the trifoliate orange is forming its own tree – and could crowd out the grapefruit grafted on its roots.

Trifoliate orange – named for those three-part leaves – is among the most cold-hardy citrus. So, it’s often used as rootstock to give tender grapefruit and other citrus a little more cold tolerance (especially in Northern California).

The fruit is covered with soft down. Usually packed with seeds, it eventually ripens to yellow and looks like a small orange but with skin that feels like a peach.

As for taste, it lives up to its bitter nickname.

My advice: Get out the pruning shears.


0 comments have been posted.

Taste Summer! E-cookbook


Find our summer recipes here!

Newsletter Subscription

Sacramento Digs Gardening to your inbox.

Local News

Ad for California Local

Thanks to our sponsor!

Summer Strong ad for

Dig In: Garden Checklist

For week of Oct. 1:

Make the most of this cooler weather. Get to work on your fall garden:

* October is the best month to plant trees, shrubs and perennials. Plants become established – sending down deep, strong roots – faster in warm soil.

* Divide and replant perennials. Add a little well-aged compost and bone meal to the planting hole, but hold off on other fertilizers until spring. Keep the transplants well-watered (but not wet) for the first month as they become settled.

* Now is the time to plant seeds for many flowers directly into the garden, including cornflower, nasturtium, nigella, poppy, portulaca, sweet pea and stock.

* Plant seeds for radishes, bok choy, mustard, spinach and peas.

* Plant garlic and onions.

* Set out cool-weather bedding plants, including calendula, pansy, snapdragon, primrose and viola.

* Reseed and feed the lawn. Work on bare spots.

* Dig up corms and tubers of gladioli, dahlias and tuberous begonias after the foliage dies. Clean and store in a cool, dry place.

* Treat azaleas, gardenias and camellias with chelated iron if leaves are yellowing between the veins.

* Clean up the summer vegetable garden and compost disease-free foliage.

* Harvest pumpkins and winter squash.

Taste Spring! E-cookbook


Find our spring recipes here!