|I have started an avocado plant from seed. When it was 7", I trimmed it back to 3". Now it is almost a foot tall. I planted it in a 10-1/2" diameter terra cotta pot with catus soil (for rich humus). But the leaves are completely limp. I water when the soil is no longer damp. I placed the plant in front of a south facing window. Am I watering too much or too little? Or what else is wrong?
Avocados are tropical plants but they grow surprisingly well in the average home environment. Yours sounds unhappy, but I'm not sure why. Is it in a cold draft? Maybe a heat vent is blowing on it? Here are some general guidelines for sprouting and growing an avocado - perhaps within these guidelines you'll find something you did (or didn't do):
Sprouting an avocado pit is easy, and the plant grows well indoors. Begin with a fresh pit from a mature avocado and carefully rinse any fruit that clings to the outside of the pit. Then just barely puncture the outside of the pit with
tree toothpicks, about midway between the flat bottom and pointed top of the seed so you can suspend the seed in a glass of water. Only the bottom half needs to be in the water. Perch your space station looking avocado pit on the rim of a drinking glass and fill with water. The top of the pit should be above the water line. After a few weeks a sprout should appear from the top of the seed and roots should begin to form in the water. Change the water every week to keep it fresh.
Once the sprout has developed two leaves, transplant your new tree into a pot filled with regular potting soil and keep your new tree in bright light (but not direct sunlight at first). Once it has adjusted to being in a pot, move it to the brightest location you have. When the stem is about 12 inches tall, pinch out the tip to encourage branching. The result will be a multistemed plant. If you don't pinch out the top, you'll get a tall, skinny, leafless stem will foliage appearing only on top.
Give the seedling plenty of light, the brighter the better. You will need to repot it into larger containers as it grows or it will quickly become very unhappy! Fertilize it with the low rate of a liquid plant food periodically. Keep the soil moist but not soggy and your plant should do well.