Soil Fertility

The left side of the picture was planted in loose organic potting soil in a 2 gallon pot. The tops did not have as much tendency to vine and the stems were thinner. Each plant produced about 6-7 patios ranging in size from 3/4" to 1.9". The biggest is about 1/2" to 3/4" smaller than typical store bought sizes. Right side of the picture shows results of Purple Patios planted in sandy soil flower bead near the house. Not as much organic matter as compared to the organic potting soil. The harder sandy soil produced lush tops with thick stems that turned into long vines that lay on the ground. The Patios produced were none to one per plant with the size between 1/4" to 3/4".

Both were planted at the same time 19 April about 3 to 4" deep. Both spots receive about the same amount of sun light of 3-3.5 hr./day. About 1/2 of the plants had died off by 29 Aug (4 months latter). Both were watered and feed nutrients at the same rate. None of the plants flowered during this time. Next time I plan to plant closer to the surface and once the plant gets about 8" high then add about 6" of loose mulch for the patios to grow in. Apparently they need lots of loose room to grow in. I need to find a better patio to give more result for the effort. Mike

Not much I can say Mike, you've done a great job of experimentation and observing the results. About the only thing that comes to mind is that it would appear that something the potatoes need for foliage is in the sandy soil while something that they need for tuber production is missing in the sandy soil. I would suggest that next time you mix some of your sandy soil with your organic potting soil. The rate of 1/3 sandy soil and 2/3 potting soil should work. This should help in increasing the size of your tubers. (You need good healthy foliage to feed the tubers!)

Another thing comes to mind: you used a 2 gallon pot? You might be crowding the plant a little - hence the smaller size of your tubers. Try to keep a few of these tubers for next year. (They will be adapted to low light conditions.) Excellent work!

Roger