This is my crop of potatoes for 2021, harvested July 14. They’re nice-looking and they’ve been delicious, so I can’t call it a disappointing harvest entirely. But I would have liked more of them! This was my first try at growing potatoes in straw, a technique I’d heard good things about. I’ll probably try it again, but I’ll adjust my approach.
You can read about this technique multiple places on the internet, but here are the basics:
- Prep a bed by clearing weeds, loosening the surface soil, adding a bit of fertilizer or some compost, and watering until it’s moist.
- Place your seed potatoes on the soil surface, about a foot apart.
- Pile loose straw on top of the potatoes, about six inches deep. (Make sure it’s straw, not hay, or you will end up with a bed of grass.)
- Wait. If it doesn’t rain, water occasionally.
- It may take a few weeks, but eventually the potato plants will grow up through the straw. Cover them with straw again. Keep doing this until you can’t pile on more straw.
- Let the plants grow, watch for pests, water as necessary, and when the plants start to die back, harvest by pulling the straw aside. Potatoes should be growing all through the hill of straw.
Here’s what my plants looked like through various stages of growth:
As expected, the plants attracted Colorado potato beetles.
I squished plenty of eggs, larvae, and adults, and seemed to have a handle on them after a short effort—but I grow in a community garden, which means that unless everyone kills off their beetles, the survivors keep coming. Eventually I just couldn’t keep up, so in mid-July, I decided to harvest. The plants had not died back yet, but I’d checked under the straw and knew there were at least some potatoes, and I didn’t think there would be any leaves left on the plants in a week, so it was time.
Not exactly a bountiful harvest:
All the potatoes I found were at soil level; there were none further up. I think the straw hadn’t broken down enough for the plants to put out roots higher than the soil.
And guess what else I found a lot of in the straw:
Turns out all that loose moist straw is a great refuge for slugs. It wasn’t just the beetles eating the plants.
Next time I try this, I’m going to put the whole bed under hoops and floating row cover. That’ll keep the beetles off and give the plants a better chance at staying vigorous. I’ll also have to come up with a strategy to keep the slugs at bay, while at the same time keeping the straw more uniformly moist so it will break down faster and promote more root growth higher up the plants. The potatoes I did harvest are beautiful; most of them were just a little on the small side. Easy to roast whole!
One more try with improvements will tell me if this technique is worth it for me. If you’ve grown potatoes this way successfully, let me know!
By Erica Smith, Montgomery County Master Gardener