Share This Page

garden q&a: too much moisture ruins crop

| Saturday, Feb. 23, 2013, 9:00 p.m.
A sweet potato vine and flower with some curled parsley. Jessica Walliser

Q: My question is about my sweet potatoes. They were very deformed with big ridges and grooves in them again this year. I would like to know what is causing this. They taste OK but look awful and don't keep well. Even some of the smaller ones were like that.

Someone told me it was because they were done growing in dry weather and then rain came and they started growing again, but I am not sure that is the problem. Thanks for your help in advance.

A: Too much water at the end of the growing season is indeed the reason your sweet potatoes are cracking. When the vines begin to die back at the end of the season, gardeners are often tempted to irrigate, thinking it will somehow prolong the life of the vines and lead to the production of larger tubers. But, instead, this practice causes the interior of the tubers to swell and crack open the skin.

Irrigation should stop three to four weeks before harvest. Though you can't control the weather, you can control excess irrigation. Splitting also sometimes happens in poorly drained soils.

For your best chance of a successful sweet potato crop, begin by choosing short-season varieties. Purchase only certified-disease resistant slips (starter plants) from a reputable source, and locate the plants in the hottest part of the garden. Plant the slips three weeks after the danger of frost has passed, and space them 12 to 18 inches apart.

To warm the soil, build an 8-inch-high ridge to plant them in, or cover the soil with black plastic for a few weeks before planting. The tubers are ready to harvest a few weeks after the vines have died back. They are a long-season crop — taking 100 plus days from planting until harvest.

Sweet potatoes prefer hot, dry conditions, which do not consistently occur here in Western Pennsylvania, making a good sweet potato harvest a hit-or-miss proposition. Still, homegrown sweet potatoes are amazing and well worth the effort.

Horticulturist Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio. She is the author of several gardening books, including “Grow Organic” and “Good Bug, Bad Bug.” Her website is www.jessicawalliser.com.

Send your gardening or landscaping questions to tribliving@tribweb.com or The Good Earth, 503 Martindale St., 3rd Floor, D.L. Clark Building, Pittsburgh, PA 15212.

TribLIVE commenting policy

You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.