How can I grow avocado successfully as houseplant?
I have, rather had, an avocado I started from seed as a house plant. It was about 1.5 years old and about 18" tall. The leaves were green and healthy and it was just about to open up another set of leaves when all of a sudden, total collapse. Within 4 days it went from green to green/crispy/dead. I live in MN and had it on a table next to a southern window. The soil was a commercial potting soil and I used Miracle Gro to fertilize it about 2 weeks prior to it's demise. The only thing I can think of is the cold snap we got on Jan 6. Could the plant have been too close to the window or could the fertilizer been the culprit? I know the plant did not freeze. Any ideas? I've got a much smaller tree going and want to avoid the same mistake(s).
I have grown avocados from seed in the past. I do not think the fertilizer was the problem; if you over-fertilized, the plant would have responded within a few days. However, to be on the safe side, use one-half the rate that Miracle Gro recommends when fertilizing your other plant. Indoor plants do not need a lot of fertilizer.
It is possible that the plant was too close to the window and suffered chilling injury. Avocados are cold sensitive. The next time you have a cold snap, measure the temperature indoors right next to the window, so you will know the actual temperature for future reference. I'm sure you know not to let the leaves touch the window glass.
Indoor avocados have a finite lifespan. I think the largest one I ever grew was 24 inches and maybe 2 years old. Your plant may have simply reached the end of its indoor life span.