Possible to grow sweet potatoes in towers?

Question

This year I will be planting potatoes (Yukon Gold and Russet) as well as sweet potatoes.

This coming weekend I will be building so-called "potato towers" for the Yukons & Russets using the designs prescribed in this YouTube video. I purchased actual seed potatoes for both varieties and plan on having one Yukon tower and one Russet tower. Fingers crossed.

As for the sweet potatoes, I bought them at an organic food store and I've been following this Dengarden article for starting the slips. Basically I took a few sweet potatoes, cut them in half, and stuck them in tin foil trays full of growing medium (quality soil & organic veggie fertilizer mix). And I've been keeping them on warming pads for the last few weeks, out of light.

Most of the sweet potatoes have now grown these long, ragged, purple "slips" (or is it chutes? I can never tell the difference!) and these slips have started to grow small green leaves.

The Dengarden article (linked above) wants me to wait until the leaves get a little bigger, and then stick them in mason jars full of water so that root systems have a chance to grow. Then it wants me to plant them into a container or directly into the ground.

But I'm wondering: can I skip the mason jar step and just build a "Sweet Potato" tower and plant these sweet potatoes the same way I'm planting the Yukons and Russets?

My hope here is that I can just build a small tower for the sweet potatoes, where a wooden post keeps a cylindrical wire-mesh container upright, and I fill it with layers of straw, growing medium and my sweet potatoes which now have long purplish slips begin to form leaves.

Is this a possibility or do I need to pick the slips off and place them into mason jars as the Dengarden article suggests? And if so, how do I know when they are ready to be picked off and placed in the jars? Thanks in advance for any-and-all help!

Answer 1

Yes, this is a possibility, you can do as you suggest and treat the sweet potatoes as white potatoes and there is a chance you can get a crop. However the devil is in the details and there are a number of things that make the process more difficult with the sweet potato.

• White potato is a cool weather short season crop. In temperate zones it is quite easy to grow regular potatoes and bring them to a mature crop in say 4-5 months and get them mature before the frosts come to kill the tops. Sweet potato is a warm to hot weather long season crop that does not fit so easily into a short season, so keep this in mind depending on your location.
• Planting rooted slips of sweet potato will get your plants growing much faster than the chitting method with white potatoes. The key factor is that roots have been established. Additionally the sweet potato tubers are attractive to vermin such as mice and voles. If the voles find your towers contain pieces of sweet potato then those pieces will soon be gone. From the surface you can't tell that the tubers are being eaten, the foliage is unaffected. Better hope that your roots have begun before the tubers disappear otherwise you get nothing.
• Once you have grown sweet potato for a season or two you will find that this plant grows a wide spreading mat of foliage, much wider than the spread of a white potato haulm. While you might get enough effective foliage from a tower with regular potatoes, planting sweet potato in a context where the flat fan of foliage is in effect cut in half or worse you are bound to have a lower crop than if it can spread in all directions simply due to the amount of sunlight falling on the foliage.
• Sometimes regular potatoes are grown specially for particular reasons such as "new potatoes" and special colour varieties. In that case the size of the crop is not as important as your main crops. I don't think the same markets exist for oddball sweet potato, although there are varieties of Ipomoea that do better in specific areas.

I started my answer positively and now will end it negatively. You can do as you suggest but depending on your location the chances of success are 0-20%. It is worth a try with a couple of towers, you will learn so much!

Update: for Zone 5a ideally your slips would be rooted and ready to go out as soon as the last frost has gone. Rooting in moist warm soil is better than rooting in water (unless children would benefit from the learning experience), so moisten some potting soil (or your regular garden soil if nicely draining) and put slips in pots in a warm bright window not in direct sun and keep them humid and warm through the night. Plan on letting them grow in the soil to fill the pot and plant out the entire root ball when soil is warm.