How to care for Ipomoea 'Black' (Manihi Maple Black) in winter?

Rosana1

Hello there,

I bought a Maple Black a while ago mainly because I needed a climber and I love the colour of the leaves. It was super healthy, with some new growth(green leaves). Then I discovered this big name stands for sweet potato, and I also found some attached to the root.

It is planted in a partial shade area, and it doesn't really get rain straight on it, but depending on the wind, it can get very wet.

Winter has started, very cold nights and very wet week. I've noticed the lower leaves are getting floppy and changing colour while the top ones look very healthy.

So my questions are:

Are these changes winter related, is it normal to change colour and fall like that?

Should I pick the sweet potato(not sure when to do it and if it is the right size) or can I just leave it there till it's bigger?

I have mulched the pot. Should the sweet potato be covered or not?

Can I feed the plant with Seasol seeweed heath treatment or do I wait till days get drier?

I hope the photos are clear enough.

Kind regards,

Rosana

JacobZ

Hi @Rosana1,

As you've discovered, your plant is actually an ornamental sweet potato vine, so finding sweet potatoes attached to the roots is completely normal.

The lower leaves yellowing, changing colour and becoming a little floppy is also fairly common as temperatures cool down. These plants thrive in warm weather and can slow significantly through winter, often shedding some older foliage while the newer growth at the top remains healthy. It doesn't look too concerning, particularly as the upper growth is still looking vigorous.

As for the sweet potatoes, there's no need to harvest them immediately. You can leave them attached and allow them to continue developing. Since the plant is being grown primarily for its foliage rather than as a food crop, many gardeners simply leave the tubers in place unless they're repotting or dividing the plant.

Mulch is fine around the pot and over the root zone. There's no need to expose the tubers, and a layer of mulch can actually help moderate soil temperature and moisture levels, which is great over the cooler months.

You can certainly apply Seasol. It's a gentle plant tonic rather than a fertiliser and can help support root health and reduce stress. Just be mindful not to overwater during the cooler months, as growth will have slowed and the potting mix will stay wetter for longer.

Overall, if the newer growth is healthy and the stems remain firm, I'd be inclined to keep an eye on it through winter and expect it to put on stronger growth again once the weather warms in spring.

Jacob