Question
How big a pot should I start the avocado seed in after I've sprouted it in water?

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Followup To
Question -
I started an avocado pit a while back in a glass of water with toothpicks. After it sprouted I planted it in a 12-inch pot indoors and I now have a small sapling about 2 1/2 feet tall with about half a dozen beautiful green very large leaves. The problem is that the stem is far to thin for the plant to support itself. Each of the leaves is very large and heavy and while the plant keeps growing upwards, the stem shows no sign of getting any thicker. I have it tied loosely between two poles. If I hadn't done this the tree would have snapped in half already under its own weight. The tree is already putting out four new leaves, thus increasing its top-heaviness and danger of breaking. Is there anything I can do to encourage the stem to thicken? I'd hate to lose this beautiful addition to my home garden.
Answer -
When I read "12-inch pot" I didn't need to read much further. That is what is wrong. The pot is too big for your small starter plant and it is not going to get any better the larger it gets in that large pot. So here is what you can do to help it. First take it out of that pot and put it in one just large enough to fit the roots in, with just enough soil around them to keep them from touching the sides of the pot. I can not tell you what size that is, without seeing the roots. Make sure you are careful when handling the roots. I put the soil in the pot, nearly to the top. Then make a hole in the center of the soil by pressing it to the sides and bottom. Then carefully hold the plant so that the roots are in the hole, and are in the position I want at the top of the pot, and with the other hand, I carefully add soil to fill the pot around the roots, and gently press to get the air out. Then water thoroughly.
I would prune the new growth. Let the plant "rest". No water, until it shows signs of wilt. No fertilizer until next May. Very bright light. As bright as you can find.
Every day gently move the stem, in the same way a breeze would move it. Don't tie it to a support, but instead lean it on a support, then move the support around as it grows. Turn the plant frequently so that the light hits all sides.
It will be a slow repair, so be patient.
If this sounds like too much bother, it would be just as easy to start a new one.
bakerplanter


Answer
The pot should be only slightly larger then the seed and roots, so that they are not touching the sides and bottom. When it fills the pot with roots,and touchs the sides and bottom, then transplant up to the next size pot. This method should be used with all container plants, as they grow. It not only makes for a stronger plant, but it also allows the plant to be watered more effiently. You see, with a larger pot the water tends to drain away from the roots, and the plant is left dry. With a smaller pot, the water is directed to the area where the plant can use it. If on the other hand the plant becomes "root-bound" the same problem occurs. The pot fills up with roots, and the water drains away. So it is just as important to make sure the plant is potted up before that happens.
bakerplanter