I have had the best harvest of Sweet Potatoes this year, it has been the best crop I have ever produced. From an area of just 3 square meters I got 12kg of fantastic looking, sweet tasting ‘Beauregard’ Sweet Potatoes that live up to their reputation. Yum!
What I did to get this great harvest: Before I planted I emptied one of my compost bins onto the plot and dug it in thoroughly. I also added some blood and bone, a bit of mixed fertiliser and gave it a good digging in as well. What I ended up with was a soil mix that was high in organic matter and ready to have my potatoes burst out of the ground.
To finish the preparation of the plot, I created two ridge mounds along the plot about 30cm wide, placed the drip irrigation in place and covered it all with a layer or sugar cane mulch. I planted two small tubers just below the surface and then waited for the shoots to appear. Around 10-14 days later when the shoots were about 40cm long I took some cuttings and planted them along the top of the ridges at 35-40cm spacing. When the ridges were all planted I then dug out the 2 tubers and tossed them away.
Here is the trick with planting Sweet Potato cuttings: When you bury them, make sure that 85% of the stem is underground. Only leave the tips poking out of the soil. This enables the stem underground have lots of roots develop along their length. It also is where the Sweet Potatoes develop and hopefully swell into big fat spuds.
Throughout the growing season I only gave them a light dose of seaweed fertiliser on three occasions. I did however have to give the runners a good trim now and again so that they didn’t grow too vigorously and creep into the bedroom at night and strangle me as I slept. They are rather energetic growing plants and you have to let them know who is boss!
I have learnt from previous years growing attempts that there is always a lot of long thin pencil shaped potatoes that develop from the roots that grow along the runners. This is quite annoying because you want all of the goodness that the plant creates to go into the big fat ones that you want to harvest at the base of the plant. So, I learnt a simple way to fix this little problem. Every couple of weeks I would gently lift all of the runners off the ground and snap off the young roots that were developing on them. If you grow on raised mounds like I do it’s easy to determine what to lift and what to leave alone.
I planted them in November and harvested them early May. I now have Sweet Potato wedges, mashed Sweet Potato and a fantastic Sweet Potato and Fennel soup frozen in the freezer, and heaps of fresh ones still to eat. A very rewarding result. Now to do even better next season…………