Kitchen Garden Forum

How long do I have to leave my sweet potatoes before harvesting? I have some in potato growing bags in the greenhouse and some growing in the open ground. Frosts here are usually rare (notwithstanding the last winter). They were bought mail order in May, grown on in pots and then planted out in June.

I haven't grown these yet, but will be interested to learn the answer, sometimes they produce slips when I forget to use them up, these take quite easily but I didn't plant them out cos I thought it was a bit too late for planting, I might try again early next year, how tall do they grow?

They don't grow very tall but they do spread out. Hope there's someone out there who can advise how much longer I should wait to harvest them - I can't wait to see what's been produced. Hope I'm not completely underwhelmed

The advice is generally to harvest when the first frost turns the foliage black. Grown oputside, that means they have had 4 or 5 months in the soil in this country, assuming they are planted in June. If you've had yours under glass or polytunnel, you might get a crop earlier, but it will probably benefit you to wait and get bigger tubers. If I had 20 plants, I'd dig one up at the end of the month to examine progress.

In the past 2 years I got my slips from the OGC and they didn't really perform too well. I lost several between unwrapping andplantiung and last year of the 10 I planted only 3 survived. This year my slips came form T&M. I was careful to get them into tepid water as soon as I received them, and of the 30 I got 25 planted with 22 surviving and after all this rain they really have started spreading out in earnest. Fingers crossed, come October we might have a good crop for a change!

Well done you! Thanks for the information. I got mine from Garden Bargains.com! 12 Plants which all survived. I shall have a rummage around in one of the containers in the greenhouse at the end of the month as you suggest. Those in the ground outside I will leave. If we have a mild winter we may not have a frost till early next year, if at all. I will have to lift them by November I think because otherwise slugs and things will eat the tubers.

Hi - we've grown sweet potatoes for the first time this year, in potato bags outside. The temptation to see what was beneath the soil got too much last week and we emptied out 1 bag. We had several good sized sweet potato and quite a few quite thin & long specimen's. I shall now leave them til the end of the month before taking a further look.

That's making me really impatient now! But I shall resist temptation for another 3 weeks. Tell me, did you feed yours much/at all? I read somewhere that they don't need too rich a soil but have given the container grown ones the odd liquid seaweed feed.

I fed them with our homegrown liquid feed - comfrey leaves that have been left in a large container of water for some time - it really stinks but seems to work well.