Thursday, December 26, 2019

Preparing pecan seeds for planting next Spring

    Next summer,  I plan to grow some pecan seedlings from seed so I can eventually expand my pecan orchard.  The seed I'll be using this year came from my pecan breeding block and is basically all the nuts that were too big to fit in my pecan cracker (size 15 pockets). I'm sure I'll get a lot of variation in seedling vigor from this seed source but I plan to rouge out any runty seedlings by mid summer.
    Pecan seeds need to go though a process called stratification before they will germinate properly. I start this process by placing all my seed in a large plastic tub (photo above).

    Next, I fill the tub with water and allow the pecans to soak overnight (photo at left). The pecans will float to the top. To ensure that all the nuts stay submerged in water, I place another plastic tub (same size) on top of the nuts then weigh it down with additional water to press all my seed nuts under water. Only fully hydrated seed will sprout into trees.

     Pecan seeds also require a chilling period to release them from seed dormancy. However, the seeds must not be allowed to dry out while in cold storage. To accomplish this, I line the bottom of a plastic storage container with moist potting soil (a mixture of peat moss and pine bark), then place a layer of well soaked nuts on top (photo at right).

    I then cover then nuts with a layer of more potting soil. I make sure all the nuts are fully covered (photo at left).
     Next, I add more pecans on top (photo at right). Once I create another layer of seed nuts, I'll cover those nuts with another layer of potting soil. I repeat the process until the box is full and the final layer of seed nuts is covered by potting soil.
    I ended up getting 4 layers of seed nuts in each storage box (photo at left).
    The final step in seed preparation is to label the seed box with the date the seed will begin their cold treatment (photo at right).  Yes, I was stratifying pecan seed on Christmas day. The sun was shining and it was over 60 degrees outside. I couldn't think of a better present to give my family than the promise of a new pecan orchard.
     The final step in the stratification process is to place the seed boxes into cold storage. Pecan seeds need to be held at 33 to 40 degrees F  for 90-120 days before they will germinate uniformly. If you use a standard household refrigerator to stratify your seed, open the lid of your seed box once a month to make sure the potting soil isn't drying out. If the soil feels dry, simply sprinkle on some water to re-wet.  
    My seed nuts should be ready for planting in late April just as outdoor temperatures start to warm up.