Can a seedling and scion be grafted from the same tree? Let's say I get an avocado from my tree and grow the seed. When the seedling is grown (root stock), can I then get a scion from the same tree and graft it on the root stock? Will that tree bear fruit like an avocado tree with a root stock and scion from a different tree?
No, it will be the same tree.
Often, the rootstalk is a variety that is hardier than the upper part or scion. Here is more:
https://www.gardeningknowhow.com/garden-how-to/propagation/grafting/rootstock-information.htm
In 2007 I took the pit (seed) from a Florida avocado and put it in some water. After the seed sprouted I planted it in our garden. In 2012 we moved and I transplanted the avocado tree to an inside corner of a fence in our villa. The avocado tree is now about 25' high. A few years ago during a long freeze the avocado tree lost all its branches. However, new growth was fantastic. We have never seen an avocado. This year the tree for the first time had many, many blossoms. However, no avocados and all blossoms are gone. What can I expect from this tree? The tree continuously drops some leaves so if I can not expect any avocados in the near future I may as well cut it down to save all the clean up effort.
If you do not know whether your avocado is a type A or type B, then you may need to have a type B tree around. They will be self-fertile on more occasions, and will pollinate a type A, as well. Here are some articles that will help:
https://www.gardeningknowhow.com/edible/fruits/avocado/pollinating-avocado-trees.htm
https://www.gardeningknowhow.com/edible/fruits/avocado/avocado-tree-with-no-fruit.htm
I just got it in March and it has grown 2 feet already. It is in a pot. How can I make the trunk stronger?
It sounds like the tree doesn't get full sun. Anything less than 8 hours of direct sunlight, or equivalent, will cause a spindly tree. Otherwise, test the soil for nutrient deficiencies, though these will appear as lesions or spots on the leaves rather than stem elongation.
Here is an article for more information on the care of the tree:
https://www.gardeningknowhow.com/edible/fruits/avocado/indoor-avocado-plant-care.htm
This collection of articles will offer more information:
Can you tell me why all my avocados go black whilst growing on the tree. They are not fully grown yet but they have all turned black
They look ripe. Small fruit can be due to genetics, or lacking in phosphorus and potassium. Be sure that appropriate conditions are being provided to the tree for the best fruit growth. Here is a collection of articles that will help:
I grew this tree from a pit and has done great until now. The bottom leaves are turning brown and falling off. Please advise. Thanks, Barbro
Make sure you are not over-watering and the soil is well-draining. Also, when you do water, water deeply to flush out accumulated salts and excess fertilizer.
These articles should help:
https://www.gardeningknowhow.com/edible/fruits/avocado/avocado-houseplant-care.htm
https://www.gardeningknowhow.com/edible/fruits/avocado/avocado-pests-and-diseases.htm
I'd like to train vertical growth and have a specific question about cutting a lead horizontal growing branch.
These articles should help:
https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=12051
https://edis.ifas.ufl.edu/publication/MG213
http://ipm.ucanr.edu/PMG/GARDEN/FRUIT/CULTURAL/avocadotraining.html
It's fine for now I cover it last nigt. November 7 because we had our first frost . I have had it for 3 years in spot inside, but this year I put it in my raise bed garden and it's a tree.
Georgia gardeners can grow dwarf avocado trees outdoors in containers, taking advantage of the long growing seasons and hot weather. Leave the container trees outdoors through much of the year but bring it inside with grow lights when cold (below 50F) as the tree is tropical and not cold hardy... which is why only container grown trees are recommended for Georgia. They can be damaged, if grown outdoors, by frosts and freezes in zones colder than 9 or 10. If you use pinching of the tips of all branches every 3 months, a dwarf avocado tree may be kept compact enough to bring indoors in winter.
https://www.gardenguides.com/139418-grow-avocados-georgia.html