How to Grow Tree Aloes (Aloe barberae)
On a recent trip to Santa Barbara, I was surprised to learn how easy it is to grow Aloe barbarae, perhaps the best-known tree aloe. The how-to info here and in my new video are from renowned horticulturist Jeff Chemnick of Aloes in Wonderland, a must-see destination for succulent lovers.
Why You Should Grow Tree Aloes
If you have room in your garden and your climate is mild with a maritime influence, consider adding a tree aloe or two. Aloe barberae (aka Aloe bainesii, Aloidendron barberae), Africa's largest aloe, is sculptural, intriguing and dramatic. It's also a great source of the partial shade so desirable for soft-leaved succulents.
A tree aloe's leaf clusters cast starburst shadows.
Nurseries may sell rooted, boxed specimens for thousands of dollars, but like most succulents, Aloe barbarae starts readily from cuttings---even large ones several feet long and branched.
DLB in wonderland
At Aloes in Wonderland I descended into a forest of mature Aloe barbarae. It was a surreal experience: South Africa in Southern CA. Not quite Alice-in-Wonderland, but certainly a wonderland of aloes.
In the aloe forest. Just out of view is the Cheshire Cat.
After the Fire
Jeff explained that when a wildfire destroyed his previous home in 2008, it also damaged a large Aloe barberae. When he removed the tree to make way for new construction, he salvaged its intact limbs. "I dug holes and stuck them in the ground," he recalls. "Like post holes, as if you were building a fence."
Jeff admits it was an experiment. He had no idea what would happen. "The rains came, and the cuttings rooted and started to grow," he says. He discovered that under optimal conditions, in-ground tree aloes grow up to two feet per year!
Success Tips
Here's what Jeff advises for Aloe barberae and similar Aloe 'Hercules' (a thicker-leaved x Aloe dichotoma hybrid):
Sun
Provide plenty of sun, ideally on a slope that's not north-facing (too shady).
Space
Give lots of room. Trunks and bases get massive over time, so don't plant close to buildings, pipes or pools. Avoid crowding a young specimen with more vigorous shrubs that might smother it.
Good Soil
Plant in fast-draining, loamy, sandy soil. The ideal pH is neutral or slightly acidic. These aloe trees like compost, too.
Water
Don't irrigate during cold, wet months. For optimal growth and flowering, water sparingly (once a month) up to weekly during hot, dry spells.
Cold protection
Cover when frost is predicted, especially when trees are young.
Fertilizer
In summer, apply a cactus-and-succulent fertilizer high in nitrogen, ideally with trace elements and micronutrients. "I use Peter’s, Scotts or equivalent, 21-7-7 in a 25 lb. bag, water soluble, for use with an injector," Jeff says.
Aloe barbarae propagation
Limbs with branches and leaf clusters ("truncheons") nearly always root, and having a small tree from the get-go is well worth a try.
Although some people prefer to let cuttings or truncheons dry several weeks, then root them in coarse sand (such as decomposed granite), Jeff plants them immediately. "They might take a few months to root and the leaves will fade somewhat," he says, "but once the leaves turn green again, you’re off to the races!"
Visiting Aloes in Wonderland
Aloes in Wonderland nursery, Santa Barbara
Jeff's home nursery is a landscaped, 4.5-acre botanic garden in which every plant is for sale. Yes, earth-moving equipment is sometimes needed. And yes, he'll whack off a tree aloe limb for you.
In addition to aloes, Jeff specializes in cacti, euphorbias, agaves and other large succulents; bromeliads (notably dyckias and hechtias), and cycads (which resemble stiff-leaved, upright palms). He also leads plant-habitat expeditions to Mexico and beyond.
So, what did I bring home?
Above is my new vining Cyphostemma quinatum and---to make the Mad Hatter green with envy---an Aloes in Wonderland T-shirt. Hey Jeff, maybe do a ball cap?
Related Info on this site
Aloes: Uses, Photos, IDs & Varieties
Aloes: How To Grow & Varieties All about aloes plus a photo gallery of aloes ID’d and in bloom See All Succulent Types Aeonium Agaves Aloes Cactus Crassula Echeveria Euphorbias Ice Plants Kalanchoe Portulacaria Senecio About Aloes There are dozens of species of Aloe, from tall trees to dwarf cultivars. Aloes typically have juicy, triangular leaves…
So what are the zone and hardiness you can grow these types of aloes the article didn’t say?
Zones 9a and 9b.
I’ve always been partial to growing New World succulents, mostly agaves and echeverias. But in the last couple of years I’ve started an Aloe thraskii (Dune aloe) and Aloe ramosissima in my yard here in the Inland Empire of southern California. Both were given to me by a neighbor who is also a succulent gardener. I like how fast-growing they are.
Hi Tim — Good to know. I think we’re going to see more large aloes in gardens as people become aware of them. I think both of those qualify as “tree aloes” (as do other species) but I didn’t include them here because that’s not their common name. But maybe I’m splitting hairs and should do a post on “treelike aloes.” Thanks for commenting!
Someone down the street from my mother in Cave Creek Arizona just planted one of these _ probably about 8’ tall. They currently have a temporary shade structure over it.
Can’t wait to see how it does in the hot Southwest! (9B). Thanks for the cool video!
There are actually 48 Tree aloes in Group J in the Kew Gardens “Aloes The Definitive Guide”
Thanks Andrew — I believe Aloe barbarae is the only one with the common name “tree aloe.” But I see your point and I’ll change the title and text to be more specific. Hopefully I’ll be able to do a more extensive and inclusive post later on.
My 8′ Aloe Barbare was planted in a sunny location in my yard, almost one year ago. A large hole was dug in preparation with sand, gypsum and cactus soil added as we have hard clay in our yard. It is on a hill, with drainage out of the low side of the planting hole so that water would not overly accumulate in a hard clay base. This summer was hot and many of the leaves curled and turned orange, and it seems very dry. I have trimmed many of the dead leaves. I am having a hard time discerning if my problem was too much water or not enough. It is tempting to water when soil is dry and yet I know that too much water is a problem. There is still new green growth at the top, with more green on the shaded side of the tree, but most of the foliage is not a green color as it was when planted in my yard. It is definitely struggling.
I would love some comments about what I should do to help bring my tree back to health.
Hi Chris — It may depend on a factor you didn’t mention: Your location. In Southern CA if you’re too far inland, the leaves can sunburn in summer, especially after transplanting. Roots may not yet be able to hydrate the leaves adequately (give it a few years to acclimate and settle in). Your soil prep sounds like you did some research, but I’m wondering what kind of sand (coarse, I hope, and not beach sand) and why gypsum. (See my page on soil.) The rule of thumb is to water thoroughly (a good soaking) during the dry season once a week or so, and not at all during winter rains, short days and cold nights. Is there softening of the trunk at ground level? That’s an indication of overwatering which has led to rot—in which case cut above the damaged tissue, let callus, and reroot the tree as a cutting. Don’t plant in the same spot, though, where harmful microbes still exist.
Hi Debora, thank you for your thoughtful reply. It is almost September and it has been in the ground for almost two years. It was a not doing well. Your questions to me- what type of sand? Course, the kind that would be found in sand bags. Gypsum was added because I have very solid clay soil under the tree. Gypsum is supposed to help with this however I suspect that the clay is so hard that is does not allow for drainage. The leaves are curled and orange with brown spots. It is still growing green from the top however they quickly curl and change color. So sad. I don’t water it much yet I cannot figure if it is getting too much or too little. If it does not drain I can only presume that is the biggest problem. Is looks sunburned so I am now covering with root barrier fabric so hopefully this will help. Would love to send you a picture…
These are amazing trees, they can sell for thousands of dollars in Australia. They are very rare, I have only ever seen then three or four times in people’s gardens, one of them was a waterfront mansion.
I managed to get a small potted cutting off Ebay for $30. I have a couple questions.
When you say “don’t plant these near buildings”
How close is too close?
Are the roots invasive?
Will they damage or destroy the foundations of buildings?
Do they see out water and will they invade pipes?
Hi Debra. Like Adam H, I am also in Aus. Have been trying to find these to grow as they look fantastic!
How often and in what season do they seed? Do they seed when they flower?
A house nearby to mine has these out the front and if I ever see them seed, I will ask to take some (wouldn’t feel right to ask to cut a truncheon)!!
Here in Southern CA they bloom midwinter. Flowers are followed by seed capsules. The base of the trees can get large, so I’d play it safe and not plant near foundations or pipes.
Do you know if aloe hybrids are able to propagate from a leaf? I realize that it is possible (though slow and hardly successful) to prop aloe vera from a leaf cutting. I am referring to the aloe hybrids like the star aloes and whatnot. Thanks!!
Hi Mose — I’m no expert on propagation but as far as I’m aware, you can’t do leaf propagation with aloes. It’s all about the meristematic tissue, which I believe is only in the stem of aloes. But I could be wrong. And of course there’s tissue culture, but that’s well beyond the average enthusiast.
We bought two quiver trees about a year ago, one seems fine the othe one not. Leaf ends are brown and curling in. They are still in their bought containers. They have good drainage, they get full sun most of the morning and no sun in the afternoon. We live in KZN near the coast
Hi Tertia — Sounds like the one that’s not doing well may have root issues. Let’s see…it’s coming into summer there…why not plant them? They’ll be happier in the ground and you can see what’s going on below soil level.
Hello. Will aloe tree leaf clusters (leaf truncheons) grow back? Our garden services broke off 2 leaf clusters. Is there anything I can do to help the plant regenerate new leaf clusters on the 2 now bare branches? Many thanks!
Hi Karin — New growth may appear from the broken ends, but it’s not a certainty. There’s no way to encourage that to happen. On the plus side, you now have two new trees (or you will have, once the cuttings take off).
Thank you!
Hi Debra, you had stated above, “ Don’t plant in the same spot, though, where harmful microbes still exist.” I am getting ready to replace my dead/diseased Bainesii and replace it with another in the same spot. What can I do to rid of the harmful microbes?
Additionally, what cause the brown/black spots on the leaves and peeling barks on the branches, on the Bainesii?
Thanks!
Hi Elizabeth — If you have no choice but to plant its replacement in the same spot, dig a hole twice as large as the root ball (larger, if possible) and dump the soil where surviving microbes can’t do any harm. Prior to planting, add a few inches of pumice (crushed volcanic rock) to the bottom of the hole to help absorb excess moisture, in case that was part of the problem. As for peeling bark, I think that’s merely normal.
As to your question about spots on leaves, Aloe bainesii is more prone to them than other tree aloes. I understand it gets worse the closer you get to the coast, probably due to more moisture in the air—which would indicate some sort of fungal disease. But no one seems to know for certain, nor how to treat it. I’ll do some research and hopefully post an answer on my Pests and Problems page. Thanks for asking!
Now on my Succulent Pests & Problems Q&A Forum: Do you have black spots on Aloe bainesii (and other aloes)? Unfortunately it’s tricky if not impossible to fix. Here’s advice from aloe expert Jeff Moore, owner of Solana Succulents in Solana Beach, CA:
>>Hi Jeff, I get asked occasionally what to do about black dots and blotches on Aloe bainesii. What do you tell people? I say it’s probably a fungus, it’s worse closer to the coast, and no one knows how to treat it. (Thinking to myself, if anyone does know, it would be Jeff Moore.) Kindly LMK if you have an answer and I’ll add it to my Pests and Problems Q&A Forum. Thanks!>>
>>Hi Debra: Your description of the aloe ‘rust’ spots is pretty ‘spot’ on. It is likely a fungus, and if so the only treatment would be repeated deep waterings with a systemic, but I never do that and don’t know if it would work anyway. There is some thought that it might be a clonal thing — inherent in some plants along with a lot of sickly yellow leaves (and usually the spots as well), yet the aloes keep on growing. There are a couple of those at the Fish Market restaurant near me across from the gas station just west of the 5 on Via de la Valle. I’ve come to appreciate Aloe tongaensis over A. bainesii; less issues and better flowers, if not as big.>>
I have 2 different kinds of aloe trees, both having black spots quite frequently, and usually at the tips of the leaves. Grower said this was due to sun, but I am doubting this, as they love sun! I could send pics if you want. Any advice?
Hi Rich — Not a sun issue. I advise regarding this on my Pests & Problems page (scroll down to Black Spots).
Hello,
I have an aloe tree that I’m trying to save. It was in a pot and had substantial root rot I believe. While getting it out of the pot, all roots pulled away from the bottom of the tree. I’m wondering how high up the trunk I would need to cut in order to get new roots to grow? any advice would be appreciated.
Hi Brett — Tree aloes can be started from cuttings like other stem succulents. Cut well above any soft, translucent or dark tissue. Rot that remains can infect the cuttings. Discard the old plant, and don’t put the cuttings in the same spot. Let the cuttings callus for several days so the exposed tissue isn’t raw, then plant so they stay upright in nursery pots containing a 50-50 mix of pumice and cactus mix potting soil. You also might dip the bottom of the cuttings in fungicide diluted 50% with water, as an extra precaution. Let them root well before planting in the garden, in an elevated area or slope with good drainage.