I think I found the secret to growing amazing sweet potatoes. Seriously. It only took seven years of growing sweet potatoes to discover this trick. *Sheesh.* So come closer and I will share my newest best sweet potato growing tips.
Realize it can be simply dumb luck or Mother Nature was taking it easy on me.
Doubtful. She is pretty tough on me.
How to Grow Sweet Potatoes from a Sweet Potato.
Sweet potatoes grow from slips. A slip emerges from a sweet potato. Have you ever seen your sweet potatoes sprout? If you allow it to continue, it will look like the picture below.
I have written about growing sweet potatoes from slips from an organic sweet potato in the past. Read about it HERE. (Yes, you can grow you own slips. Why pay for them?)
Once the slips get about six to eight inches, you snap them off and put them in water to root.
In the pass, I would let my sweet potatoes simply sprout in the house. Usually this happens in March when the weather starts to get warmer. The sweet potatoes magically start to sprout.
I figured–easy peasy. Grow and snip. Life can’t get any easier. Right?
If you allow the slips to grow that early, you can’t plant them until the middle of June in zone 6. So, they will grow very long roots and the leaves will turn pale green since they need sunlight.
If you were a plant, would you want to be stuck in water instead of luscious soil? I didn’t think so.
Sometimes, the plants get white flies too while they are waiting to be planted outside.
So what is a green loving sweet potato girl suppose to do?
Have you ever heard about timing?
My Best Sweet Potato Growing Tips
I bought an organic sweet potato this year since I ate all of mine by the time it was slip growing time.
I don’t remember if I chose a white sweet potato or another orange variety. I happen to love the white sweet potatoes.
Before thinking of growing sweet potatoes, you will need a 90 to 120 days of a frost free growing season. Also plan on 8 potatoes per slip to decide how much to plant. I used 9 grow bags to grow sweet potatoes.
Here are my tips:
It takes 6 to 8 weeks to sprouts a sweet potato. Count backward to when you can plant your sweet potatoes. The soil must be warm. In zone 6, I wait until mid-June to the end of June depending on the weather to plant my babies. Organic Gardening suggests to plant 3 to 4 weeks after your last frost.
- Go to the grocery store and check out the available sweet potatoes. Choose a skinny sweet potato and variety that you like. (Try it first before growing it.) Before cooking and falling in love with it, check to make sure your gardening season is long enough to grow it. Remember, you need 90 to 120 frost free days to grow sweet potatoes. Don’t choose a sweet potato that needs 120 days when your growing season may be cut short from frost. Southern Exposure lists different varieties and length of time needed to grow.
- Choose an organic and skinny one just in case because an non-organic one could be sprayed to inhibit sprouting. Fat ones don’t grow as many slips.
- Plant the potato in a container with compost. Only add enough compost to the middle of the potato. Sprinkle some on top to keep the potato moist. (I actually use an aluminum loaf pan. Make sure to cut some drainage holes on the bottom.)
- Use a heat mat under the potatoes. I tried putting them outside in the sun versus the heat mat. The heat mat won. (You can buy one HERE.) I use my heat mat with all my indoor seedlings.
- I even put a plastic clear bag around the container to create a little greenhouse since I chose a big fat sweet potato who didn’t want to grow slips. (Yes, sweet potato panic set in really quickly.) Put the potatoes in a sunny place.
- If you want to be extra vigilant, put the potato with the plastic bag and heat mat under grow lights.
- Once the sips start to grow, snap them off at 6 inches. I don’t find bigger is better in this situation. I even snapped them off at 4 inches since panic started to set in with mid-June right around the corner. Stick to 6 inches.
- Put the babies in water and let them root. They will grow roots very quickly sometimes in less than 4 days. Keep checking. I put my slips in water in a sunny window.
- Once their roots are 2 inches long, plant them! That is the key. In the past, I would let the roots get nice and lush. Don’t!! I think the long roots cause the potatoes to form one long center one and smaller skinny ones on the side. They grow like a bunch of bananas. You want all the bananas to be the same size.
- In case you are an eager beaver and your roots get too long or you buy potted sweet potatoes, Bonnie Plants suggests “to cut each plant off just above the soil line in the container, then plant it (without roots) straight into your garden bed. The slip will form new roots in just 2 to 3 days, and those roots will eventually become fine, well-formed sweet potatoes.” I have never done this but it makes sense.
- Right after frost date, get your beds ready for growing sweet potatoes. I use grow bags with 100% compost. Grow bags breathe. Beds must have loose soil to a depth of 12 inches. You can mound your potatoes. Cover with dark plastic or landscaping fabric. You want the soil to heat up. Sweet potatoes love heat.
- Add a cup of all purpose organic fertilizer to your grow bags. (I use Dr. Earth, my favorite.) If you are growing them in beds or the soil, add fertilizer 2 weeks after you plant the seedlings. Bonnie Plants suggests 2 cups 5-10-10 per 30 square feet.
- Plant one slip per bag or 12 to 18 inches apart in a soil bed with rows 3 feet apart.
- If you are using bags, put heavy duty cardboard under them since the potatoes will try their darndest to grow through the bag. (Go to a place that sells appliances and grab some of that cardboard. They will gladly give it away for free because they have to pay for recycling.) Do not mulch over the cardboard; otherwise, it will deteriorate allowing the inmates (the roots) to run amuck. (Done this…)
- Don’t allow the leaves to root either. You don’t want any energy taken from your growing “bananas.” And yes, those darn leaf stems will root given the chance. I simply pick them up periodically. You can also grow the plants near a fence and train the stems to grow upward. It is quite beautiful.
- Once you see a flower, your sweet potatoes will be ready to harvest. One year I saw flowers in August and I knew I was in trouble. And, yes my sweet potatoes were skinny and awful. I didn’t follow my cardboard and length of root advice.
- I normally harvest the week before my fall frost date. Don’t wait until frost since it will damage the roots.
- Be very careful when removing the roots. The skin is very fragile. Gently remove some of the dirt and store in a warm ventilated area for at least 10 days. I wait until 3 weeks. You want your potatoes to cure. They get sweeter as they cure.
- I store my potatoes in an area with little sun and a colder location. They last until the next season or we eat them, which ever comes first.
Watch the video below as I empty the bags. Check out the bananas! Aren’t they gorgeous?
Join the Conversation:
How do you grow sweet potatoes?
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