Looking for a citrus you can grow in-ground in cooler climates? We’d like to introduce you to yuzu fruit — and give you tips and tricks to help you grow your own yuzu!
A quick video introduction to yuzu:
Our citrus obsession
We live in Upstate South Carolina. Until the 2023 USDA hardiness zone update, we were in zone 7b, but we’re now zone 8a. For context, during the winter months, our temperatures regularly drop below freezing.
Nevertheless, we also grow about a dozen varieties of citrus, but we have to grow them in pots. Why?
Most citrus isn’t very cold hardy. Thus, we use a pot-moving device lovingly named the Porta-Potter to lug our large potted citrus plants in and out of a heated garage as needed to get it through winter. Are we crazy? Very likely.
But once you taste a fresh organically grown blood orange, kumquat, satsuma, or other citrus you’ve grown yourself, you’ll understand our plight. Plus, our young son LOVES the all-he-can-eat citrus buffet in the driveway.
We tested the cold-hardiness of the yuzu citrus tree – here’s what we found!
Years back, we tasted the juice of a yuzu fruit (Citrus junos) for the first time. If you’ve never had it, yuzu tastes like all the best flavors from a Meyer lemon and a grapefruit combined, but unique and better. We were hooked. (Note: Yuzu is not a fruit you eat whole like a tangerine, rather you use the juice and skins.)
Then we read that yuzu was very cold-hardy. Hmm. The next spring, we ordered a yuzu sapling and put it in the ground in a warm-microclimate next to our house.
We kept quiet about our yuzu tree because we wanted to test it over multiple winters to see how it performed before promoting its cold-hardiness to other people. The first couple of winters our yuzu was in the ground were relatively mild. We had a few dips into the teens, but nothing severe. The young tree lost a lot of its leaves and had some “burned fingers,” but bounced right back by spring.
Then, the 2022-23 winter put our young yuzu to a much more extreme temperature test. We had two nights in a row where our digital thermometer registered 6°F (-14°C) and winds were too strong to cover the now 10′ tall yuzu tree. Brrr.
How’d our yuzu do? The tender tops of the branches were killed and the tree dropped all its leaves. Sigh.
But then something cool happened: about a month later, new leaves were popping out, and by spring the tree had completely recovered. Flowers formed and soon we had developing fruit!
First yuzu fruit – and first yuzu fruit freeze test
We harvested our first organic, homegrown yuzu fruit in October and November of 2023. When we saw freeze warnings in our forecast, we decided to leave some yuzu fruit on our tree to see what effect freezing temperatures would have on the actual yuzu fruit…
After four nights of freezes, including two nights that dipped to 26°F (-3°C), we harvested and tasted the fruit. It tastes no different than the yuzus harvested BEFORE the freeze. Woohoo!
With these yuzu growing experiences under our belt, we’re now going to start publicly touting the frosty wonders of the yuzu fruit. So, if you live in a cooler climate region and you’ve long wished you could grow citrus, yuzu might just be your dream come true.
How to grow yuzu fruit
Here’s everything you need to know to grow your own yuzu fruit:
Step 1. Consider your zone: where will yuzu fruit grow?
Yuzu can grow and produce fruit fairly easily when planted in-ground from zones 8-11.
If you live in Zone 7, you may be able to grow yuzu in ground in a warm microclimate, such as a sunny, south-facing wall next to a house or building. It will likely survive outside of a warm microclimate, but may only be productive during years with mild winters.
Zone 6 or under:
Yuzu might survive in-ground. If it does, it won’t be productive. Instead, in these zones, grow yuzu in a pot so you can move your yuzu into protection during winter.
Step 2. Select varieties from a nursery or grow from seed.
Yuzu is self-fertile so you only need one plant to get fruit. But what variety and where do you get a yuzu tree?
Some important context: Yuzu fruit is extremely popular in Korea, China, and Japan, and that’s where virtually all the global yuzu fruit production is based. Due to its popularity in those countries, most yuzu fruit stays there, which is why it’s so hard to find and so expensive in the United States. (Up to $5 per yuzu fruit!)
In east Asia, you can find multiple varieties of yuzu, but the juice from each variety is virtually indistinguishable. Rather, varietal differences have more to do with traits like plant height, peel thickness, seediness, etc.
Most yuzu fruit contains a lot of large seeds. However, the variety ‘Tadanishiki’ is seedless. Problem: you can’t find it in the US, and international shipping on citrus is (understandably) extremely restricted in order to try to reduce/prevent the spread of diseases such as citrus greening which are wreaking havoc on worldwide citrus production.
If you do happen upon a legal Tadanishiki yuzu in the US, scoop it up. Otherwise, get whatever yuzu variety you can from a reputable nursery such as One Green World. (That’s where we ordered our yuzu, which is a varietal called ‘Ichandrin’.)
Our Ichandrin yuzu has plenty of seeds, but also plenty of flavor. We’re happy.
Additional plant selection notes:
A mature non-grafted yuzu tree can be 15′ tall x 10′ wide. This size is fine for in-ground growing but not exactly a small tree fit for a pot. Thus:
- If you plan to grow your yuzu tree in a pot, make sure you get one that’s grafted onto dwarfing rootstock to help keep its size in check. The nursery should note the rootstock in the description. If not, ask.
- If you’re planning to grow yuzu in-ground, dwarfing rootstock might not be essential so long as you’re ok letting the tree grow larger.
Can you grow yuzu from seed?
Unlike many other types of citrus, yuzu can grow true to seed somewhere in the range of 90-98% of the time, despite the fact that it’s a hybrid between an Ichang papeda (Citrus ichangensis) and Satsuma mandarin. This is owing to nucellar embryony, wherein the seeds/offspring are essentially more vigorous genetic clones of the mother tree.
To grow yuzu from seed, get seeds from the fresh fruit rather than using older, dried seeds. However, keep in mind that starting from seed could add a few years to your wait time to get fruit versus buying a yuzu tree from a nursery that’s already a couple years old and grafted on rootstock that expedites fruit production.
Step 3. Prep your soil.
Growing yuzu in-ground?
Yuzu likes rich, well-drained soil with lots of organic matter. It also prefers slightly acidic soil, with a pH between 5.8 and 6.5. Before planting, amend your soil with quality compost, worm castings, and/or aged manure.
Also, consider NOT putting your new yuzu straight in the ground if you’re in zone 7 or 8. Young plants are less cold-hardy. Instead, baby your yuzu for its first year, then transplant it to its final location the following spring.
If you’re stretching zones with your in-ground yuzu (zone 7 – 8a), you’ll also want to select the warmest, sunniest microclimate possible.
For instance, our yuzu (pictured throughout this article) is growing next to our home (thermal mass traps heat) in the most south-facing direction possible in order to maximize winter sunlight and warmth. The spot also gets full sun (6+hours direct sunlight) throughout the rest of the year as well.
Growing yuzu in pots?
A few tips:
- Use a high quality organic potting soil like Happy Frog.
- Pot up your yuzu into larger pots every 8-12 months until your yuzu is growing in the largest pot size you can manage. For reference, “large pot” for our citrus plants means 25 gallons (about 22″ in diameter), which is the largest size we can find at Lowes or Home Depot. Tip: pot prices are steeply discounted at the end of summer into early fall, so buy them then to save money!
- Make sure your yuzu pot has drainage holes at the bottom to ensure good drainage, otherwise the soil will become waterlogged and anaerobic, eventually killing the plant.
No matter where or how you’re growing your yuzu, these tips apply:
- Don’t bury the trunk or you can sicken or kill the tree. Instead, plant the yuzu tree in the prepared soil at the same depth it was growing in its nursery container.
- Keep a ~3″ layer of mulch over the soil surface if you’re growing in-ground or a 1″ mulch layer if you’re growing in a pot. Mulch protects the soil, boosts biological soil fertility, evens out soil moisture and temperature, and reduces weed pressure. Taper the mulch off near the trunk so it’s not buried.
- Apply a good organic citrus-specific fertilizer like Jobe’s at least every 2-3 months, and more frequently when the plants are rapidly growing and developing fruit during the spring and summer months. (Citrus is a heavy feeder.) Top-dress compost around the perimeter of the tree each spring, then top-dress mulch over the compost.
4. Maintain ideal soil moisture with irrigation.
Yuzu trees prefer consistent soil moisture but not wet or waterlogged soil. Too much water will cause root rot, potentially killing the tree.
In-ground yuzu tree irrigation notes:
- 1″ of water per week is needed, either via rain or irrigation.
- Young trees (1-3 year old) grown in-ground are more susceptible to drought and/or lack of water than mature, established yuzu trees.
Potted yuzu irrigation notes:
- We have almost 20 potted citrus trees, so we use drip irrigation on a timer. Drip irrigation saves a ton of time, let’s you leave town without hiring a tree sitter, and ensures your citrus stays happy. See: How to set up drip irrigation for your potted fruit trees (including citrus)
- Like other citrus, yuzu plants grow fairly quickly, and the roots will fill and begin circling the pot. Eventually, this will cause them to become “rootbound” (basically strangling themselves), which makes them very hard to water, feed, or keep alive. Potting up your growing yuzu ever year until they’re in their final pot size is necessary. Then, root-pruning at least every 2-3 years will become necessary. See: How to root-prune potted citrus, with video
Inadequate watering may cause fruit drop or fruit quality issues, so get this part right!
5. Maintain your trees (pruning, cold protection, pest & disease management)
Prune as and when necessary
Prune your yuzu trees to remove dead or diseased branches and to maintain ideal shape. Pruning can be done in late winter or early spring before new growth emerges.
Protection from cold
It’s easy to protect potted yuzu trees. Simply lug them indoors or into a garage when freezing weather is on the forecast.
However, protecting in-ground yuzu trees from deep freezes isn’t so easy. The first step is planting them in a warm microclimate to start with, as detailed earlier.
You might also be able to cover them with frost blankets when they’re smaller. Our yuzu is too tall to cover or wrap and our deepest cold weather almost always comes with blustery winds which blow the covering right off the plant anyway.
Another option is to use organic, OMRI listed foliar sprays like FrostShield, which can help insulate your yuzu against cold weather and can’t be blown off!
Pest and disease management
Watch for common citrus pests such as aphids, scale insects, spider mites, and citrus leaf miners. These are typically more of a problem for potted indoor citrus, not outdoor citrus.
Treat any infestations promptly using organic sprays. Our personal favorite is neem oil.
There are also some citrus “pests” that we tolerate and don’t consider pests. For instance, butterfly species such as giant swallowtails use citrus as a host plant. If we see their larvae on our citrus, we’ll move them from our prized citrus plants to our experimental hybrid citrus plants.
6. Harvest your yuzu.
How long does it take yuzu fruit to ripen?
From flower bud formation to perfectly ripe fruit, it takes yuzus about 7 months to ripen.
When does yuzu fruit ripen?
Yuzu fruit typically ripens in late fall to early winter. Ours (we just got bumped to zone 8a) ripens from late October through early November.
How do you know when yuzu fruit is ripe? Can you eat unripe yuzu fruit?
Perfectly ripe yuzu fruit turns from green to fully yellow. You can eat slightly unripe yuzu fruit that’s mottled green-yellow, but it’s not as good as the fully ripened fruit.
How do you harvest yuzu fruit?
When fully ripe, yuzu fruit will pop right off the tree with a gentle twist and tug. Wear gloves so those spines don’t get you!
7. Eat your yuzu fruit
The best part and what you’ve been waiting and working for: eating your yuzu fruit!
Each type of citrus is used and eaten differently. For instance, you can eat kumquats and calamondins whole, skin and all. Blood oranges and satsumas are peeled and the delicious low- or no-seed fruit is eaten piece by piece. Makrut/thai limes are prized for their leaves.
So how the heck do you eat a yuzu fruit? First you juice the small 2-4″ diameter fruit.
What does yuzu juice taste like and how do you use it?
Yuzu juice tastes like a delicious, sour combination of lemons and grapefuits, but much better. It’s hard to explain how good it is until you try it. A few ways we use fresh yuzu juice:
- Watered down and sweetened with stevia to make the best lemonade you’ll ever taste (yuzuade?).
- Added as a flavoring to drinks, salads, or anything else you use lemon juice for.
- As the acid in ceviche or aguachile.
Can you use yuzu peel – how?
Nope, you’re done yet. Yuzu peels are amazing for culinary use as well.
Warning: Only use organically grown yuzu peels since citrus tends to get a lot of synthetic pesticide sprays under conventional production.
8. Store your yuzu fruit.
If you’re going to use yuzu fruit within a few days, you can store them at room temperature. Otherwise, store them in your fridge, where they can last much longer – up to a few weeks.
If you have more yuzus than you can use soon or you want to store them for months, they can be frozen whole in a freezer bag. Or you can freeze the juice in an ice cube tray and store the cubes in one bag and the skins in another.
Answers to frequently asked questions about yuzu:
What are other uses for yuzu?
Outside of their use as a flavoring in foods and beverages, yuzu fruit (including the skins) are used in various hygiene and cleaning products. Also, in Japan, an interesting use for the fruit is as a “yuzu bath,” aka yuzuyu.
Yuzu fruit is added to hot bath water, releasing the juice, essential oils, and aroma. Traditionally, yuzu baths were taken during the winter solstice for various health benefits, including relaxation, cold prevention, and improved skin quality.
Is yuzu high in vitamin C?
Yes, yuzu is very high in vitamin C. Per 100 grams of juice, it contains 40mg of vitamin C. 100 grams of yuzu peel contains 150mg of vitamin C.
One study found that “mature yuzu contains higher amounts of vitamin C and phenolics than other citrus fruits.”
Are there other cold-hardy citrus varieties?
Many types of citrus are frost-tolerant. Some can tolerate light freezes. However, no type of citrus thrives through a deep freeze, even yuzu.
In addition to yuzus, there are a few other cold-hardy citrus varieties:
- Trifoliate orange (aka hardy orange) is probably the most hardy citrus. According to University of Arkansas Extension Agency, it’s hardy to -10°F (-22°C). It’s endemic in many areas of the US, and is famous for growing in Monticello, Thomas Jefferson’s garden in Virginia. When we’re out foraging, we often see trifoliate orange growing in the wild here. However, the fruit quality is not good – almost all seed and extremely sour. It makes a great citrus rootstock though!
- Ichang papeda (aka yuzu’s baby daddy) is a rare citrus plant that has comparable cold-hardiness to yuzu. The fruit isn’t as good as yuzu though.
- There are some varieties of satsuma and kumquats that are fairly cold-hardy as well. However, they’re not as cold-hardy as yuzu.
Now you have the information you need to grow yuzu fruit! If you give it a shot in your garden (or pot) we hope you love it as much as we do!
More helpful articles for pot-heads (no, not that kind!):
- How to root-prune potted fruit trees, with video
- Video tour: potted citrus garden in Ag Zone 7b (now 8a)
- Step-by-step: how to grow your own organic citrus at home in any climate zone