Why aren't my seedling apples budding out?

I have two seedling apple trees (two years old, meaning this will be their third summer) that I think may not have the correct number of chill hours. Neither has budded to this point in the season (mid April), although the stems appear to be alive. Neither has developed side branches to this point in their lives and both are about 18 inches tall.  They are probably siblings. The seeds came from a batch of applesauce / dried apples a few years ago.

One was planted in a tree pot against a south facing fence, the other grew on its own beside a sidewalk. I moved that one this spring, but if the problem is chill hours I moved it to precisely the wrong location (against a south facing cement wall).

I'm guessing that because of where they were (are) growing they aren't getting the chill hours they need.

Any suggestions or ideas? Other possibilities? I'd really like to save them, since they likely came from a tree with fruit that doesn't brown easily.

Hmm, I'd really suspect that in your climate zone in Utah that you got enough chill hours.  Can you find out how many chill hours you did get?  And then reduce it a bit to account for the microclimate you put them in?

Apples seem to be the last things that bud out for me.

I bet they're just still sleeping.

Not sure about what your weather is like, but we've had quite a few days in the 80s and some of my apples are just now waking up.

I'll add to what Steve said above, I have a Winesap in a pot that is going into it's 3rd summer since grafting and it is just starting to stir now. It also has no side branches yet.

I have a seedling apple in a pot that is one year younger that is all leafed out, and a mutzu in a pot the same age as the Winesap and one in the.ground and both of.them are in full bloom.

So it could well just be a variety that comes out of sleep later (which seems like a good trait in Utah, no?)

Three of my seedling apples are leafed out. Two are not. One died (its first winter, not unexpected). I was thinking that because they're seedlings the required "chill hours" might be different. They all have different genetics, although all came from parents that survive in this area.

On the chill hours all I found was an historical average (2200).

So I guess I'll just wait and see.

Oh yeah, chill hours shouldn't be your problem then.  Most apples need 500-1000 chill hours so you should be well over that.  Maybe if you were in St. George it would be a problem...

Its really unlikely your going to buds on seedling apple trees that are 2-3 years old. They are just too young seedling apples are going to grow to full size and be really large trees so they just dont flower that early. Doubt you will get anything for atleast 10 years or so.

Leaf buds, not blossoms, are my concern at the moment.