Help for the Home Gardener from the
Contra Costa Master Gardeners' Help Desk
with trellis attached to fence
I've recently purchased a potato vine. As I was planting it, I noticed that the bottom of the trunk looked strange. I think I'm seeing exposed roots and if so, what should I do about it? I'm planting the potato vine to trellis along a 20-foot fence line. See photo. at right. This was my first attempt at a vining plant, and I'm not sure about planting it in a pot. How should I trellis the vine? Maybe I should buy a second vine to span the distance. Thank you.
Advice from CCMG Help Desk:
Exposed Roots: Typically, it‘s recommended to plant nursery plants at the same level they were in the nursery pot, so as not to bury the crown (where the roots meet the trunk). However, your particular specimen seems to be a bit unusual. If it came from the nursery like this, it seems that it was planted too shallow in the nursery pot, with some roots exposed. At this point, we might suggest that you add mulch (good quality compost is great for this purpose) to your container to cover some of these exposed roots, but not above the crooked base which appears to be the crown. Whenever using mulch, it should not be placed too close to the base or trunk of plants and trees, as this can lead to crown rot or other diseases.
with roots exposed below the crown
Training the Potato Vine to the Trellis: The Sunset Western Garden book indicates that this variety of potato vine can quickly grow up to 30 feet. However, in a container, this vine may not grow to that length. Vines with twining habits will wind their stems around a support by twisting or spiraling new growth as it elongates. Using ties to train your vine along your trellis is a good idea. You will want to bend young growth while it is still green and supple and wrap ties around both the trellis and stems. Once the stems have wound around the trellis, remove the ties or move them further down the trellis. Additionally, the potato vine can be cut back heavily at any time of year to remove unwanted top growth and promote vigorous new growth. To achieve your desired effect, regular attendance to this training will be necessary.
It is difficult to determine the distance of your trellised fence from the picture, but it might be a good idea to add another vine to cover this area more quickly. Or, you might move your container to the middle of the trellis area and train the vine to grow in both directions.
Growng Plants in Containers: Consistent watering of container plants is necessary, especially in the summer months. Most container-grown plants still need moisture in the winter, though not as much.
Your container plants will also need the addition of some fertilizer over time as the nutrients initially available in the potting soil are depleted or washed out of the pot. Applying a general purpose or controlled-release fertilizer can be used as recommended on the manufacturer's label.
With some attention to the training and care of the vine, you should have a very impressive trellis. If Master Gardeners can be of further assistance, please do not hesitate to contact us.
Editor's Note: The CCMG Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. (map) We can also be reached via telephone: (925) 646-6586, email: ccmg@ucanr.edu, and we are on the web at http://ccmg.ucanr.edu/. "Ask a Master Gardener" help tables are also present at many Farmers Markets as well as at the CCMG's "Our Garden" programs (map). See the CCMG web page for details/locations.