Those sound tiny. They'll probably need to grow at least another year, maybe two or three before you can use them as stock -- guessing. Depends on how fast they grow for you.

I'm thinking the trunk of the rootstock needs to be at least 3/16" to 1/4" before you can graft onto it. But that may depend upon the type of graft you are doing -- you didn't say. Budding? Whip graft? The larger the rootstock diameter, the easier it will be. I prefer at least 3/8" diameter for bud grafting. For bud grafting you have to be able to peel the bark.

Dave that shows that I have no clue what i'm talking about. I thought for the beginning the easiest would be to make a slit in the rootstock and slip the graft in, tye together and just wait. Dreaming??

T-budding is the easiest to learn and generally the most successful. Virtually all citrus "grafting" is done in that manner, at least in areas where rooted cuttings is not the preferred method. Rooted cuttings are fine for container growing; but not so good in ground, with some varietal exceptions, such as Kaffir. The size of the rootstock is not so important when doing T-bud; the most important is that it is actively growing. Most of our budding here is done on rootstock that is just under the size of your little finger.

so that means as long as I keep the tree in a pot there is no reason to graft? And here I thought it has to be done to keep size manageable or manipulate taste of fruit.

Grafting/budding is done to change the rootstock from the native/natural root to one that is more resistant to soil pathogens or structure; those things do not normally occur in container growing, hence the rooted cuttings or seedlings being okay for containers. Rootstocks are also used at times to increase or decrease the size of the tree depending on their relative aggressiveness or lack thereof.

Susanne, i am surprise that you did not take me up the offer of 4 F/d for just postage a week ago or so.

New Zealand lemonade was grafted to a US897 rootstock seedling about a 1/2 year old and 3/32 inch diameter

New Zealand Lemonade on US897 grafting · More Info

New Zealand Lemonade on US897 grafting · More Info

New Zealand lemonade on US897 rootstock. · More Info

C35-Fukushu-Node53 · More Info

C35-Fukushu-Node53 · More Info

C35-Fukushu-Node53 · More Info

Susanne, I have done cleft grafting even on 5 month old rootstock. The graft took and after some time I gifted the tree to my friend. If I find those old pics, I will post them here.

Bob I'm so sorry I totally missed that. Is this offer still good???

Susanne, the tube box with pryorty mail is like a triangle box that is either 36" or 48" tall. I might be able to jamb 4 F/D in there with heavy pruning. The little tree's are about 4 years old, nice size for grafting. I'll see what i can do.

Bob that would be awesome. How can I contact you? No idea how this private message system works

eSilviu that is just awesome. I would looove to try that too. What are Cotyledons? I seeded some grapefruits a couple od days ago and they already sprouted. Two for each seed. I would love to use the as a rootstock for practice. Your method seems to be the most appropriate for me for now. (not wanting to wait four years ;). )

eSilviu, nice work, could you show the graft line on that Clementine tree.

Graft line is almost invisible when graft is made on very young rootstock

Found-it?

Here it is:

very impressive. I wish I will be that good someday :)