Looking back through my hardcopy garden journal, I was surprised to find that we'd planted this Robinson crabapple tree in 2006. It sure didn't seem like that long ago. (Time flies when you're having fun---or getting old ! which is more my case.) Anyway, looking through the journal jogged my memory about this poor tree's history. Dave bought it on a 75% off sale at Lowe's. It was half dead when he brought it home and someone had cruelly carved the branches out of the center. We planted it in August in the midst of a drought and babied it to keep it going. In 2007, it budded and was just beginning to leaf when a late spring freeze nipped it back. Needless to say, no flowers and what branches grew were spindly. The spring of 2008 was kinder to the poor tree, no freeze but regardless, it refused to flower. The branches thickened a bit but it still looked scrabbly. After it went dormant this past fall, I gave it a good pruning. We had all but decided to move it if it didn't bloom this year. . .
Barring a killing frost to nip the flower buds, a flowering tree that refuses to flower can be coaxed. In the fall before it goes dormant, hit it with a dose of phosphate and then again around the end of February before it gets the chance to bud. I used ferti-lome Blooming & Rooting Soluble Plant Food. It's ratio is nitrogen (N) 9%, phosphate (P) 59%, and potash (K) 8%. Another method is to purchase phosphate by itself and work the powder into the dirt around the tree. High Yield makes a phosphate for just that purpose and it is also good for working into the dirt around gross feeders such as dahlias or peonies.