The sun has come out and daytime temperatures are starting to rise into the 80's. With this kind of weather, I start to get anxious to see my pecan grafts break bud. Today I visited the first graft I made this year (photo at right). This graft was made back on Wednesday April 24th; that's 20 days ago. As a rule of thumb it usually takes three weeks before the buds on a new graft start to pop. However, the first half of May has been unusually cold and damp. I may not have bud break yet but it looks like the buds on my scion have started to swell.
Two weeks before I started grafting pecans, I grafted about 70 apple trees. Apple trees start growth earlier in the Spring (than pecans) allowing them to be grafted earlier (usually early April). My apple grafts weren't phased by this Spring's cool damp weather and all my scions are showing good growth (photo at left).
I wanted to show you the difference in graft performance between pecan and apple to make a point about the nature of pecan trees. Pecan tree growth and graft callusing are enhanced by warm temperatures, especially high night-time temperatures. During the first two weeks of May average over-night lows dropped down into the 40's. Apple trees don't mind the cool temperatures and grew just fine. But pecan trees just seem to stand still in cooler weather.
However, this week we are forecast to receive ideal temperatures for pecan graft growth. Highs in the 80's and lows in the 60's. Pecan is a warm weather crop and seems to require higher over-night lows both to start growth in the Spring and fill out their nuts in the Fall.
It won't be too much longer until I start to see new shoots developing on scions and the little green bud on the scion pictured at right will be growing like crazy.
