Every year, I tweak my method
of growing sweet potato slips. Year 1, we put sweet potatoes in
partially filled glasses of water and they rotted, so year 2 we
added a heat mat under the glasses. The heat mat tempted
several of the sweet potatoes to sprout, but I was disappointed at how
late the slips showed up --- we didn't fill the last of our sweet
potato beds until early July. So, last year, I
started the slips at the end of March...and the roots sat there
until April, producing slips during the same time frame as they had the
year before. I also lost several tubers last year since I chose
big roots that were less inclined to sprout.
This year, I made yet
more changes to my sweet potato propagation method. I chose
tubers that were about two inches in diameter at the widest point and
placed them beside the incubator for two weeks to
preheat. Monday, I dug about a gallon of small
gravel out of an eroded wash above the alligator swamp and filled up a
seed-starting flat, laying the sweet potatoes on their sides and then
packing damp gravel between them. I added the clear top on the
flat to keep the contents moist and slipped a heating pad underneath to
promote sprouting instead of rotting.
In case you're trying to
decide if sweet potatoes are worth growing, I'll throw some numbers out
there. Conventional wisdom, repeated all over the internet, holds
that white potatoes give you the most calories per acre, but in our
garden last year, we got just over 6 pounds of sweet potatoes per
garden bed, which comes to 2,379 calories. In contrast, we
harvested 6.5 pounds of white potatoes from each bed, but the white
potatoes have fewer calories per pound, so they lost the race at 2,034
calories per garden bed.
That said, the greatest
number of calories I've ever harvested from one
garden bed was a tie between a
bed yielding 13.5 pounds of carrots fall before last and the 3.5
cups
of amaranth seeds I threshed in the summer, both clocking in at just
over 2,500 calories. Clearly, white
potatoes aren't the only high calorie food you can grow in just a bit
of space. I wonder which other oft-repeated tidbits of gardening
lore aren't precisely correct? The moral of the story is --- try
several different kinds of high calorie crops and choose the ones that
match your soil, climate, and taste buds.