Problems with avocado plant

(Question)

Hello!

I grew my avocado plant from a pit just over a year ago. It lives in an apartment with north facing windows – not the best, but it was growing well. It was potted just before winter, and I water it thoroughly every two weeks or so. A few months ago during the winter, the lowest set of leaves started to brown at the edges. I moved the plant a few feet away from the windows because I was afraid it was getting too cold, and then the browning seemed to have stopped. Those leaves didn’t fall off though, and then spring came and the plant continued to grow again after some sort of winter hibernation. A few days ago, I noticed that the pit has turned black, and there’s a hint of browning of the main trunk/stem right above the pit.

1. The pit turning black isn’t normal, is it? What could be wrong with the plant and what I can do to help it recover?
2. Any insight regarding the browning of the leaf edges would help.
3. Most of the leaves are quite big and pigmented, so they don’t look unhealthy, yet all of them are “droopy”/doesn’t remain upright, almost looks like they are growing downwards. What could be the cause?

Thanks very much

(Answer)

Growing an avocado plant from the seed, or pit, can be very rewarding— for those with patience, that is, as the germination period can be weeks… and months. Nonetheless, you clearly passed the first hurdle, and not only that, have your plant potted. Well done ! The next challenge, as you are facing now, is to sustain the growth of your plant, as avocados are REALLY sensitive.

First, watering. Avocados need consistent moisture, slightly on the drier side, and need very good drainage. Maintaining these conditions can be a real balancing act. You mention that you “water thoroughly every two weeks or so”. You didn’t specify the size of the pot or type of growing medium you have used,  but it is possible that your plant has received too much water. If this is the case, it may have developed root rot, or fungus. If the roots are not healthy, and are at risk, then it will not be possible for the roots to process the flow of necessary nutrients, and water, up to stem and to the leaves.

Secondly, the growing medium. A re-potting of your plant may help rectify several inter-related  issues. With your hand spread over the top of the soil surface, upend the plant, carefully slide off the pot, and take a good look at what’s going on with the root system and the soil. The recommended PH for avocados is 6.0 to 6.50, and they also like a slightly acidic soil. Further, you can promote good drainage by blending some large mulch into your potting soil: this will allow oxygen to reach the roots. This, in turn, relates to your question about the browning of the leaves, which can occur under waterlogged conditions, or when the soil is too compact. Regarding the pit, it should have served its purpose, once the plant’s root system was sufficiently developed. It will likely disengage from the stem during re-potting.

Fully mature, fruit-bearing avocado trees grow large downward-sloping leaves, and they serve to protect the fruit below the leaves from being scorched by the sun’s rays — in California and Florida, for example. On this note, your avocado plant will need adequate light intensity to thrive, but at the same time doesn’t like the high-and-dry heat of indoors, so spraying the leaves would likely be welcomed by your plant.  Good luck with your avocado plant, and if all goes well, in 7 to 15 years it might be a fruit bearing tree !