I recently got a comment on this video where a viewer asks why her sweet potatoes are wilting and have yellow leaves:
So – are these sweet potatoes going to make it?
“Hey David! I am a new gardener (new to veggies, anyway) – and I grew my own slips from an organic sweet potato from Publix, planted them in early June, and have been gleefully watching them grow. (I live in Orlando, BTW.)
I’m starting to freak out a bit because the other day I noticed that I had a few yellow leaves – I pulled them off and didn’t worry. But then I looked out there at about 5:00 and noticed that the entire bed was horribly droopy. It looked like a human had just laid down and rolled around in the bed or something. Then about 20 minutes later, the sky started to cloud over and they stood back up. I’ve been watching them closely and they are fine in the morning and evening, but pretty droopy when the hot sun is on them. I thought it was just the sun and heat, but I started reading online about fusarium wilt.
I’m FREAKING OUT that that’s what it is. More leaves are turning yellow, but I’m still getting new growth and the vast majority of leaves are green. I’m finding some dead, brown leaves underneath, but I don’t see anything wrong with the vine stems. The bed is pretty crowded. (I did a raised bed, 4×4 and about 8″ tall, put thin cardboard down and dirt on top. There was sod under the cardboard.)
Do you have any advice?
I will be crushed if I don’t have any edible sweet potatoes come November. Thank you so much – I have one of your books and I love it, so I’ll be getting more. :)”
More Photographic Evidence
Here are a few more pictures Kerri sent:
Here are the sweet potatoes when all is moist and cool:
And here they are when the sun is beating down:
Normally, I only post garden pictures from readers wearing pink flip-flops, but this time I made an exception.
Why are These Sweet Potatoes Wilting?
Over the many years I’ve grown sweet potatoes, I’ve never had a problem with fusarium wilt or other nasty diseases. They’re easy to grow, particularly in Florida, and so long as you don’t keep growing them in the same place they usually produce a yield.
If the soil was hot sand, they might only give you little roots… but this soil looks very nice. I don’t see any signs of herbicide damage or serious insect problems, either.
The hot sun is tough on plants with tender leaves, such as sweet potatoes and pumpkins. These sweet potatoes are also in a hot microclimate judging by the white wall behind them. If you’ve ever gotten a crazy sunburn while out on the water, you know how reflective surfaces can be tough on your skin. The same is true for plants.
That said, I don’t think the wall is a big deal.
But What About the Yellow Leaves?
If there were a lot of yellow leaves on these plants I would worry. This just looks like the normal growth of sweet potatoes to me. As they age, they drop some of the older leaves and put out new ones.
There was a possibility that they were overwatered (overhead irrigation can cause some rot); however, Kerri wrote me in an email and headed off that possibility:
“I know I’m not supposed to be watering them much – it’s not raining as much as it should this year, so if it doesn’t rain once a week I water them.”
She’s also concerned about the rotten brown spots here and there on the leaves.
In my experience, all this is normal with sweet potatoes, particularly as the summer rolls on. Florida is hot and humid. There are lots of insects, fungi and other things that can damage your sweet potatoes.
Yet this damage is usually overcome by the plants. I’ve had some really awful looking vines produce quite serviceable roots for the table.
My advice: if the spots and yellowing get a lot worse, make up some compost tea with fresh compost plus some yogurt, kefir, kombucha or other living ferment; stir it up, then pour it or spray it over them all the next day. That often heads off disease issues.
For now, stay the course and keep doing what you’re doing, Kerri. I think you’re going to be fine. If everything looks perfect, you’re probably in a laboratory!
There’s a reason I plug sweet potatoes heavily in my popular book Totally Crazy Easy Florida Gardening. They usually take a lickin’ and keep on tickin’.
Good luck and let me know how they turn out – and thank you for reading.
Does anyone else see anything I missed? Ever get fusarium wilt on your sweet potatoes? Is there another issue? Let me know in the comments!
That’s what my seminole pumpkins look like mid afternoon before this low pressure thing moved close and provide cooler afternoons… I planted some at a neighbors and she’s almost pulled them up a couple times… I said ‘NOOO! They are fine! They can’t move to the shade so it’s how they cope…’ So far, so good…
Yeah, they should be fine.
I see the little holes in the leaves: makes me wonder if the air potato beetles have discovered her plants. Florida has released air potato beetles to combat air potatoes: those vines that drape themselves all over everything. Kudzu.
The air potato beetles attacked my ornamental sweet potatoes and ruined a good share of the leaves. So I pulled them up and gave up on it because I was growing them for the pretty leaves. The beetles didn’t destroy the roots though.
The beetles did destroy quite a bit of the air potato vines in our swamp but the vines came back this year.
Your sweet potatoes look more like an ornamental variety? I think the air potato beetles don’t go after the orange and purple sweet potato vines as much as they do the ornamental ones. I have orange, purple, red and white sweet potatoes as well as the ornamentals.
Or maybe you have Boniato: the leaves on Boniato are a little different as well. You might want to switch to regular orange sweet potatoes if you have a bad problem with air potato beetles. Although, I think your sweet potatoes will grow just fine underground even if the leaves look ragged.
Just my two cents…
I’ve never heard of the air potato beetle eating sweet potatoes. They are not closely related species at all – that would be very bad if so. Thank you for the comments, Cynthia!
Thank you, David! I am so relieved to hear this about my beloved sweet potatoes! 🙂 When I was watering them more, I was watering from above, so I’ll be sure to water under the leaves from now on.
I cannot WAIT to have sweet potatoes in the fall! Thank you, thank you, thank you for your help! I appreciate your time. Your gardening expertise has been wonderful for me. 😀
Sorry I wasn’t wearing pink flip flops. I have purple, so I’ll wear them next time. 😉
Ha! Perfect. Make sure to send in photos when you harvest.
Great article, David. I’m brand new to your site. I’m thoroughly enjoying each and every article you have written. I’m learning so much! Thank you for giving us your precious time and sharing your knowledge. You truly are inspiring me to try different things and use different methods. I am extremely grateful for the hours and hours you must spend writing all this wealth of information.
In appreciation – Bobbie
P.S. I just LOVE your sense of humor — don’t stop and for sure don’t let the nay-sayers drag you down. Obviously they don’t have a life! Just my 2-cents.
Happy Day To You ~~
Thank you, Bobbie. I appreciate it very much and thank you for finding me.
One more question: can I trim the vines? They are starting to overtake the area around the bed. LOL. I prepared the bed next to the sweet potatoes and beans for fall with cardboard, compost, and soil a month or so ago. And then I realized that I need to be able to get all the way around the beans, so I won’t be planting in that bed until the beans are gone. (I should have amazing soil by then!) However, the sweet potatoes are encroaching there and some of the long vines have white roots on them! Should I let them go and root in the soil? Or can I trim them so they’ll stay in the bed? I don’t want to damage anything but I figure that the potatoes grow underground…so trimming the vines might be ok. They’re pretty crowded in the bed. (And they have over a month to go!)
Thanks again, and sorry for all the questions! You are just a wealth of information! 🙂
I pull up the overflowing vines, little roots and all, and just toss them back over the border and into the bed.
Can you give us a crash course in curing? There’s lots of information on the Internet, but I need info specific to Florida.
Can I put them on my screened in porch in a single layer, so they’re in the humidity but not the sun? For 2 weeks? And then in a basket…or paper bag? In the garage – it’s still hot and humid there but it would be dark. How long in the garage?
Then…bring them into the A/C and put them in bags in the pantry to keep for months. I planted them in early June, and I’m going to check on them today to see how big they are. I know you said you pull them in November, but that would be 5+ months and I’m afraid they’d be too big.
Do you recommend planting something else in the sweet potato bed or just planting sweet potatoes again there next summer?
Someday I’ll stop asking questions about sweet potatoes and move on to asking questions about something else. HAHA! Thank you for all your help!
Will see what I can do.
I also have this variety of the photo, but I do not know her, can you tell me her name, please?