Strawberry tree height and spread

Living and farming here in San Diego, I often feel like we won the lottery with our growing conditions. We have this incredible Mediterranean climate that lets us get away with growing plants that would shrivel up and die in the rest of the country.

One of my absolute favorites—and one that constantly confuses visitors to my farm—is the Arbutus unedo. You likely know it as the strawberry tree, but let me stop you right there before you start picturing vines of massive strawberries climbing up a trellis. This is a robust, evergreen tree that belongs to the heath family, making it a woody cousin to blueberries and rhododendrons.

I remember clearly when I planted my first row of these beauties along the western ridge of my property. A neighbor, a guy who had been farming avocados since the seventies, leaned over the fence and asked if I had lost my mind planting “decorative shrubs” in prime orchard space.

Alexander Mitchell

Five years later, when those trees were screening out the highway noise and producing buckets of red fruit in late November, he asked for a cutting. That’s the thing about the strawberry tree: it earns its keep, but you have to understand exactly how big it gets and how it spreads, or it will swallow your garden whole.

If you are looking to plant this species, whether for its ornamental peeling bark or its unique fruit, you need to throw out the generic plant tag info. Real-world growth in American soil differs vastly from textbook definitions. I want to walk you through exactly what to expect regarding height and spread so you don’t end up with a chainsaw in your hand five years down the road.

Botanical Identity and Varieties

The Arbutus unedo carries many names. In Ireland, where it grows wild, they call it the Killarney strawberry tree. Some old horticultural texts refer to it as the Cane Apple. But whatever you call it, you are dealing with a plant that naturally wants to be a multi-stemmed giant shrub rather than a single-trunk tree.

The name “unedo” is derived from the Latin phrase “unum edo,” attributed to Pliny the Elder. It translates roughly to “I eat one.” Historians debate if he meant the fruit is so delicious you only need one, or so distinctive (and perhaps mealy) that one is quite enough.

Here at Exotic Fruits and Vegetables, we’ve found that the primary confusion regarding size comes from people not knowing which cultivar they have purchased. The genetic variance in this species is massive. I have seen standard seedlings shoot up to 25 feet, while dwarf varieties planted at the same time barely crest the top of a fence.

Comparing Cultivar Sizes

To give you a realistic idea of what you are signing up for, I’ve compiled data based on trees I’ve grown or managed in the San Diego area over the last decade. This table assumes you are treating the tree well—giving it decent soil and occasional water.

If you have a small suburban backyard in Poway or Chula Vista, do not buy a generic seedling. Go for ‘Elfin King’. I once landscaped a small patio in La Jolla using three ‘Elfin King’ specimens in 25-gallon pots. Seven years later, they are still a manageable five feet tall and look like living sculptures. If I had used the standard variety, the roots would have cracked the pots and the canopy would have blocked their ocean view within three years.

The Truth About Height and Spread

The standard strawberry tree is not a vertical skyscraper; it is a sprawling umbrella. In its native Mediterranean habitat, which mimics our Southern California weather perfectly, these trees can eventually hit 35 feet. However, in a domestic garden, 15 to 25 feet is a safer bet for both height and width.

Expect the spread to equal the height. If the tree is 20 feet tall, it will likely be 20 feet wide. This is critical for spacing—do not plant these 5 feet away from your house foundation.

Why do they spread so wide? It’s a survival mechanism. The tree creates a dense canopy to shade its own root zone, preserving soil moisture during our long, dry summers.

The branches often start low to the ground, and if left unpruned, the lower limbs will continue to extend outward, rooting where they touch the soil in a process called layering, though this is rarer in drier gardens.

Soil Influence on Size

You can manipulate the size of the tree through soil volume. In deep, sandy loam—like what we find in some of the river valleys here—the taproot can dive deep, and the tree will maximize its size. But we also have a lot of hardpan and clay.

If you plant a strawberry tree in shallow soil over a hardpan layer, it will stop growing vertically and put all its energy into horizontal spread. I’ve seen 10-foot tall trees that were 25 feet wide because the taproot hit solid rock.

Watering: The Growth Accelerator

Many people treat Arbutus as a “plant it and forget it” xeriscape element. While they are drought-tolerant once established, drought stress halts growth. If you want the tree to reach its full height and spread quickly to provide screening, you need to water it like a fruit tree for the first three years.

For maximum growth, provide 10-15 gallons of water every 10 days during the summer months for the first two years. This deep soaking encourages the roots to anchor deeply. If you only sprinkle it with a hose for five minutes, the roots stay surface-level, the tree remains unstable, and it will never reach its potential height.

Our experience at Exotic Fruits and Vegetables has shown that trees on a drip irrigation schedule grow about 40% faster than those left to fend for themselves with natural rainfall alone. Once the tree reaches the size you want, you can taper off the water to “maintenance mode,” which effectively pauses the rapid expansion.

Pruning to Control the Beast

Pruning a strawberry tree is like giving a haircut to a sheep dog; you have to find the structure underneath all that fluff. Because the tree naturally wants to be a shrub, training it into a tree form requires early and decisive action. You need to identify a central leader (main trunk) early on.

I learned this the hard way. I once ruined an entire batch of nursery stock by pruning them too heavily in late winter, right before a surprise frost hit our valley. I opened up the canopy too much, the cold air settled into the center of the plants, and I lost about 60% of the interior foliage. They looked like skeletons for two years.

Never shear a strawberry tree like a hedge. Using electric hedge trimmers destroys the beautiful, shedding red bark and leaves you with a wall of cut leaves that turn brown and ugly.

To manage the height and spread effectively:

• Limb up slowly: Remove the lowest branches, one ring at a time, over several years to expose the trunk.
• Thin the center: These trees get dense. Remove crossing branches to let wind pass through, or the tree might topple in a Santa Ana wind event.
• Pinch the tips: If a branch is spreading too far over a walkway, pinch the soft new growth in spring rather than sawing off a thick limb later.
• Respect the collar: When removing a large limb, do not cut flush to the trunk. Leave the branch collar intact to prevent rot.

The Fruit Cycle and Aesthetics

We can’t talk about this tree without discussing why we put up with the space it takes: the fruit. The strawberry tree is unique because it flowers and fruits simultaneously in late autumn and winter. You will see white, bell-shaped flowers (similar to lily-of-the-valley) hanging right next to the red, bumpy ripening fruit.

Ever wonder why the tree seems to be in constant production? It’s because the fruit takes a full 12 months to ripen. The flowers you see today are the fruit you will eat next year.

The fruit itself is about the size of a ping-pong ball. It starts green, turns yellow, then orange, and finally a brilliant scarlet red. The texture is where people get divided. It is soft, slightly mealy, and creamy inside.

“It’s like eating a sweet, gritty peach custard that someone packed inside a red balloon.” — My reaction the first time I tasted a perfectly ripe one.

We at Exotic Fruits and Vegetables always recommend harvesting only the deep red fruits. If there is even a hint of orange, it will be astringent and sour. The red ones are sweet and contain about 20% sugars, but they don’t have a long shelf life. You have to eat them within 24 hours of picking, or process them into jams or liqueurs. This perishability is why you never see them in grocery stores.

Planting for Long-Term Success

To ensure your tree hits that 15-25 foot sweet spot, you need to plant it correctly. Here is the protocol I use for every installation:

1. Dig Wide, Not Deep: Excavate a hole three times the width of the container but no deeper than the root ball. The flare of the trunk should sit 1 inch above the surrounding soil grade.
2. Verify Drainage: Fill the hole with water. If it is still standing there after 24 hours, do not plant. You must build a raised mound or pick a new spot.
3. Skip the Amendments: Do not fill the hole with potting soil or compost. Backfill with the native soil you dug out. This forces the roots to adapt to your specific ground immediately.
4. Mulch Heavy: Apply 3 to 4 inches of wood chips under the canopy, keeping it 2 inches away from the trunk itself to prevent collar rot.
5. Stake Loosely: Only stake if you are in a high-wind area. Allow the trunk to sway slightly; this movement signals the tree to build thicker wood.

Common Challenges

The strawberry tree is tough, but it isn’t invincible. The biggest threat to its size and health is Phytophthora root rot. This fungal pathogen loves warm, wet soils. If you overwater this tree in the summer while the soil is poorly drained, the tree will decline rapidly.

If you see the leaves turning brown and remaining attached to the branches, stop watering immediately. This is the classic sign of root death. The tree is drowning.

Another issue is the Arbutus localized aphid. They attack the fresh spring growth, causing the leaves to curl and twist. While this won’t kill the tree, it ruins the aesthetic and stunts the vertical growth for that season. A strong blast of water from the hose is usually enough to knock them off. I try to avoid harsh chemicals because I want the birds to feel safe nesting in that dense canopy.

Why It’s Worth the Space

I have grown mangoes, cherimoyas, and dragon fruit, but the strawberry tree holds a special place in my landscape. It is structural, beautiful, and provides food when most other plants are dormant. The key to enjoying it is giving it the lateral space it craves—don’t try to shoehorn it into a narrow side yard.

Through our work with Exotic Fruits and Vegetables farm, we aim to help people connect with plants that offer more than just a green backdrop. The Arbutus unedo offers a changing seasonal display of bark, flower, and fruit that is unmatched.

Whether you are planting a ‘Compacta’ near your porch or letting a standard variety dominate your back slope, you are adding a piece of living history to your land. Just remember to give it room to breathe, and it will outlive us all.