Avocado leaves with dry brown edges are usually due to dry air. Source: cantikalami.club

Question: I grew an avocado tree from seed this summer and now the edges of the leaves are turning brown. Why? The plant is 30 inches (75 cm) tall and has only one main stem.


Answer: The avocado tree (Persea americana) rarely does very well under the conditions that prevail in the average home. True enough, it’s relatively easy to grow one from a pit harvested from a store-bought fruit and that’s kind of fun. Plus, it does grow vigorously at first, but it tends not to stay attractive very long … and that’s normal. Indoor conditions are not really much to the plant’s liking. It would really prefer full tropical sun and intense atmospheric humidity, things that are hard to give it indoors.

The plant most often shows its displeasure in the fall and winter, when its leaf edges start to turn brown and dry out, a condition that engulfs more and more of the leaf surface over time.

And the main cause is dry air.

The avocado comes from a humid tropical climate where the atmospheric humidity is usually at least in the 70 to 80% range and often well above that. Indoors, though, relative humidity drops seriously during the heating season. In many homes, it remains below 30% throughout much of the fall and winter. And when the air is too dry, evapotranspiration (loss of water from leaf cells) increases. Soon, the large but thin leaves of the avocado begin to lose water more quickly than the plant can replace it and when that happens, the cells begin to die, leading to browning.

Humidifier to the Rescue

To keep the leaves in top shape, you need to try increasing the humidity as much as possible and the easiest way of doing so is with a humidifier. If you can manage to keep the humidity in the 45–55% range (also, a good level for humans and pets), that will make a huge difference. Of course, this is far from the 70 to 80% the plant really wants, but at least it ought to keep all but the oldest leaves from browning at the edges.

A humidity tray can help too, although it’s more efficient on shorter plants. The humidity it gives off often diffuses into the air around before reaching the lofty leaves of indoor trees like the avocado.

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Spraying the leaves with water is just a waste of time. Montage: laidbackgardener.blog

And there is no point in spraying the leaves with water in an effort to increase humidity. The concept that spraying helps plants to cope with dry air is one of those garden myths that refuses to die.

For “perfect” growth (i.e. no browning at all), grow it in a humid greenhouse or seal your avocado tree inside a large clear plastic bag during the fall and winter. The humidity inside will be 80% and above, just perfect for your avocado. Yes, it will be able to breathe inside a sealed plastic bag. Just watch out for too much condensation. If that occurs, open the bag for a few hours … then seal the plant in again.

Note that, even if you increase the humidity, the damaged leaves will not turn green again, but rather new leaves will not turn brown. In other words, high humidity doesn’t cure browned leaves, it only prevents future damage.

Some Additional Suggestions

First, can I assume that your plant is growing in potting soil? If not, pot it up without delay. Many people start their avocado pit over a glass of water, but it won’t live forever that way. In fact, as soon as you see the first signs of root growth, you really should transplant it into a terrestrial environment.

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If you let the leaves of your avocado wilt, that too can lead to brown leaf edges, especially if the air is dry. Source: brbdyer420,www.houzz.com

After it has been potted up, regular, deep watering will be necessary. The root ball must never dry completely, because that too can lead to leaf browning. So, as soon as the soil seems dry to the touch, it is time to water again.

Also, hard water is not good for avocados. They prefer a more acid soil without excess minerals and for that reason, the water would ideally be soft. However, not only can tap water be hard, depending on its source, but the chemical treatments given to municipal water to keep it drinkable can increase its hardness. And hard water can also result in browning leaves, especially in combination with dry air.

Ideally, the water would have a calcium carbonate concentration of less than 60 mg/l: i.e., it should be soft. If your water is considered hard or very hard, it would be better to water your avocado tree with rainwater, dehumidifier water or distilled water.

Or Just Ignore the Problem

The good news is that even if you do nothing at all, the condition of your avocado tree should begin to improve all on its own in the spring, as the damaged leaves will eventually drop off and will be replaced by fresh, healthy leaves. And in the spring and summer, the air indoors in most climates is much, much more humid than in the winter: certainly at least in the 50% range. The result is that the new leaves should remain in fine shape … that is, until the next heating season.

Avocados: fun to start, but not such great houseplants. And they really hate dry air!

30 comments on “Browning Leaves on an Indoor Avocado

  1. I kept my potted avacado at 60% humidity this winter and it improved a lot at first but in the last month it has lost 6 leaves and the newer leaves are yellowing and browning. I bought a ph meter and it says my soil ph is 8! is there a safe way to lower the ph without shocking the plant?

    • Mathieu Hodgson

      I would simply repot the plant with some new potting soil which should have an appropriate ph. You could also add sulfur, Aluminum Sulfate or Iron Sulfate into the surface of the soil. Be careful not to put too much!

  2. How cold can the avocado tree stay? I keep most of my house 58f to save energy.

  3. I started using the humidifier and it worked! New beautiful leaf’s sprouted out of the top! I was so happy. However, not long after the new leafs came the tips of them started to turn gray and dry out. They all did this and eventually fell off.
    I’ve kept the humidifier, gave it plant food, made sure I didn’t overwater it and have grow lights on. What am I doing wrong?
    The tip of the tree was brown/gray (I’d post a picture but can’t)
    So as a last ditch effort I clipped the tip off with clean sheers. The inside looks very healthy and
    I’m really hoping this tree makes it but I’m at a loss.

  4. Can I put my plant outside in the sun for a few hours then bring it back inside? We have no windows that let direct sun in like the plant needs

  5. This is the most helpful advice and I have done all I can find, repot, soil they like, not over watered, next to a window (facing east, I have no windows facing south) with a grow light on it but haven’t found this information before. My poor avocado tree has one leaf left and that leaf has a little bit of browning, it does look happier since I started putting it next to a humidifier – is it too late to put a plastic bag on? If it looses this last leaf, will the tree die?

  6. This was so very helpful’ my 19” tall potted avocado tree has leaves turning all brown. They are crisp and dry. I’m going to try covering it with a plastic bag to increase humidity. I live in high desert where our water is not treated but may still be high in salts. Does flushing it through with watering help that?

  7. Pingback: Top 18 Brown Spots On Avocado Leaves

  8. Nora Russell

    Most concise l and helpful advice I’ve found on the internet for a newbie gardener! Thank you!

  9. Great article. I wouldn’t assume the obvious to people coming here on the internet- I hadn’t heard of salt- softened water before. Now I’m going to search it up to see if that’s the case where I am.
    Thanks for the article, really useful.

  10. William Yellin

    I just moved three avocado plants that I grew inside in a south-facing window from the stones in glass jars of water until they were between 5″ to 10″ high into individual pots filled with citrus potting soil. The pots are 10″ diameter and 1 foot high. Are they too tall? The pots have 6 drainage holes. I also put about a 2″ thick moss on top to try to hold moisture. Was the moss a good or bad idea? Thanks for answering my questions. You are the best source of “agricultural” information for armatures.

  11. bill yellin

    What about water run thru a water softener?

    • Definitely. To me, that was so obvious that I didn’t think of including it. You just don’t use water softened by salts on plants!

      • What do you mean by “water softened by salts”? Salt is the main medium used in water softeners to clean the media inside the softeners… does that count as “softened by salt”?

  12. k.collins

    Thanks for the explanation ! one question, my tree is approx 4ft , all leaves ,apart from some very new growth at the very top are almost brown . So now i have 3ft of bare trunk and once the others drop off there will be 4 ft of bare tree. Will this be its annual cycle? where it becomes more trunk than leaves?

  13. Nancy Proft

    Can I put my avocado trees outside for the summer

  14. Amazing, thanks for this advice. I am ordering a humidifier now! Grew this with my son and we are so proud, but after a year and a half the leaves have done just as you have described. Hopefully, we can help the plant to feel more comfortable and healthy 🙂

  15. Thanks for your clear and concise article which has answered all of our questions as to why our indoor avocado plant starts to go brown at the end of summer! Now we should be able to try to look after it better in the future!

  16. carib909

    My avocado tree leaves are turning brown in the late spring. Outside temperature is is often above 100*F.

  17. In the case that all but one of my leaves has turned brown (the second scenario which you described to be seriously browning) do I cut off the leaves. If so, do I cut a portion of the leaf and leave the green portion in hopes of maintaining photosynthesis or should I cut at the base of the leaf?

    • Leave the one leaf alone for now. Cutting it off won’t help and could hurt. Just take moderate care of the plant (avoid heavy watering, as there is only a bit of green to see moist!) and keep your fingers crossed. This is not the sign of a healthy plant, but with a little luck new leaves will appear soon… in which case you could remove the lingering one.

  18. sepdriessen

    Would it help to cut off browned leaves prematurely in order to promote overall tree growth and creation of new healthy leaves? As you mention, since damaged leaves will not be cured and will eventually fall off anyway, it seems as if removing them will prevent the tree from wasting its energy and resources on them, but perhaps my intuition is wrong.

    • You’re sort of looking at this backwards. As long as the lead carries out photosynthesis, it’s providing more to the plant than it is taking away. A brown edge only reduces its efficiency a small amount. Of course, if the leaf is seriously browning, essentially dying, yes, you could remove it. Otherwise, if it’s functional, it’s useful.

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