Since we have quite much old straw occupying the hay loft, and the maple on the frontyard is producing a great amount of compost material each fall, we decided to try to grow some potatoes in that biomass.
The straw and leaves where put directly on the Ground in early april, as the potatoes where put to germinate inside the house. Four weeks later, when the risk for nightfrost had diminished, the potatoes where scattered on the strawbed, covered with more straw and leaves, and watered.
As comparison, a few potatoes where planted using the traditional methodologies of digging them into the ground.
The first harvest was expected 8-10 weeks after germination (middle of june), but a chilly period in may delayed it with two weeks. Maybe the cover crops method is more suspectible to cold weather since it lacks the isolating features from a thick layer of soil? We don’t know, since the soilgrown potatoes is a later kind. That’s a parameter to keep track of next year.
Reflections:
Strawbed:
- Potatoes can be harvested continuously. You don’t dig up the plant, just follow the stem and roots in the straw and collect the right sized potatoes. Smaller ones are left to grow some more.
- The potatoes are very clean, and probably free from contamination from soil bacterias.
- No digging required.
- Vandalizing snails was a great concern, but turned out to be a minor problem. They seem to prefer occuring weeds like dandelions to the potato leaves. The patches with less weed were more affected by snails than wilder ones. However, young plants attacked by snails had a tougher time reaching full growth, but the harvest from them was only delayed, not diminished. Leaving mature potatoes in the ground for too long made them a decent meal for the snails, so the advice would to pick the big ones continuously.
- Some kind of radar device would be handy in finding mature potatoes in big scale cultivation.
Soil:
- Since the potatoes where left in the soil to let more of them grow big before harvest, more potatoes were damaged by snails.
- Manual labour is tougher with the soilbed. Breaking the ground (well, we did some of it with tractor and harrow), covering with soil, digging up the harvest.
- The potatoes are dirty, but the dirt may work as protection and keep humidity in the storage. We’ll see.
- Smaller harvest, since the plant gets damaged when the potatoes are dug up.
The need for watering seems to be the same with both methods. The strawbed was very moist in the lower layers, even after several weeks of draught. We watered both patches quite much after putting out the potatoes.
Neither patch has shown any signs of leaf rot. An hypothesis yet untested is that growing mushrooms among the potatoes would make it harder for leaf rot to establish. The mushrooms didn’t thrive in the heat, so we’ve prepared a mycelium to mix in the strawbed in the autumn.
Links:
- DIY GPR (ground penetrating radar) Doesn’t seem that hard to build a raspberry pi based potato locator. Even easier since it only need to be an SPR (straw penetrating radar).
- The blog about Skillnadens trädgård not far from us, has many informative and inspirational posts about cover crops.