I have a mature grapefruit tree that bears well. It was grown from seed and is at least fifteen years old. My question is could you select limbs to turn into a satsuma or orange? What would be the best method to use budding or grafting?

Yes you could graft on to existing branches , although I would loose the idea of trying sweet oranges where you live. Best method would probably be a bark graft or cleft graft

You should look at these links:

Joe Real's tutorial on bark grafting:
link

and

Joe Real's multi-grafted tree:
link


Matt

i think i read somewhere here on the forum that grapefruit as a rootstock does not produce the best fruit. lots of fruit but not very good. so maybe try different types of grapefruit,

Thanks Matt for the link to JoeReals post where he wrote,

"Bark grafting is very good to use on mangoes, avocadoes, citruses, atis (sweetsop), graviola (Guyabano, soursop), atemoya, cherimoya, mabolo, loquats, and other fruit trees whose barks can be easily peeled off when they are slipping. The barks are slipping when the plant is having a growth flush. When you see those new tender growth sprouting in most parts of the tree, the bark is slipping. So you have many chances to do this in a year under a tropical setting that have many growth flushes during the year."

and Lazz wrote,

"The bark will start to slip once you see new growth."

This helped me with the whole bark slipping thing.

Darkman, you may not be aware but I believe it is still illegal to propagate your own citrus in Florida. See Malcolm Manners response in the thread below. I believe that includes grafting onto existing trees as well.

link

Yes it is illegal but the mere possession of the knowledge and freely discussing it is still permissible at least for now. I and friends of mine have friends and relatives that live mere minutes away in sunny Lower Alabama.