Tag Archive | Wisconsin Gardening

Vegetables: Sweet Potatoes are Super Foods!

by Lisa Johnson, horticulture educator for Dane County UW-Extension

landscape-1506015991-baked-sweet-potatoes-1Did you know you could grow sweet potatoes in USDA Zone 5a, 5b, and 6 in Wisconsin? Sweet potatoes, or Ipomoea batatas, are tender, warm-weather plants related to morning glories. They come from Central and South America, and need a long, warm growing season. They grow on trailing vines, with bush-type varieties for smaller spaces.

Usually you buy what’s called sweet-potato slips, which are unrooted cuttings. They arrive by mail, 4-6 inches long, for planting in late May to early June. Soil temperatures should be a minimum of 55º F, 3 inches down for best rooting. Test this with a soil thermometer.

Strip off the bottom leaves, leaving one node (growing point) and a couple of leaves on top. Plant node-end up, 3 inches deep in mounded rows about 18-24 inches apart. Leave 36 inches between the center of each row, or plant in hills with three or four slips per mound.

If the soil is dry, water it before and after planting. Keep slips moist while rooting, but drier once established. Don’t water the last three to four weeks before harvest. Watch out for voles because they love the roots!

sweet-potatoes-freshly-dugHarvest sweet potatoes before danger of frost in late September or early October. Handle roots carefully; they bruise easily. Gently remove dirt clods without rubbing. Don’t wash them before curing.

Curing sets the skin, heals wounds, and converts starches to sugars. Curing allows the roots to store much longer than those uncured. Ideally, cure them in a warm area for 10 days at 80º to 85º F and high humidity (85 to 90 percent), or next to a running furnace for two to three weeks at 65º to 75º F. Once cured, store in a dark location at 55º to 60º F. Don’t refrigerate! Wrap cured sweet potatoes in newspaper and store in a cool closet or basement. Store properly, they can last six to 10 months!

Sweet Potatoes Recommended for the Lower Half of Wisconsin

Cultivar Name                 Days to Harvest                                   Root & Flesh Color

  • Beauregard                     100                                        light purple skin, dark orange flesh
  • Bush Porto Rico               110                                             copper skin, orange flesh
  • Centennial                      100                                                   orange skin, flesh
  • Jewell                             100                                                        orange flesh
  • Vardaman                       110                                              golden skin, orange flesh

Dividing Hostas

by OCMGA Master Gardener Holly Boettcher

HostaThe million-dollar question for serious gardeners is whether it is better to divide your hosta plants in late fall or the early spring. At our vineyard, we have massive perennial gardens which are home to hundreds of hostas. When you see me staring off into space while relaxing in one of the many sitting areas on our property, what I am really doing, is contemplating which hosta need to be divided, and where the gardens will expand into the next season.

From past experience, I have learned it is easier to “wrestle” the plant in early spring, when those tender buds are swelling through the warm spring earth. If I divide at this time, I don’t feel as though I am committing an act of violence against them. BUT, early in the spring, it is difficult to remember what that hosta looked like. You see, I am one of those gardeners who obsess over planting hostas so their colors, variegations, and shapes, will both contrast and compliment those around them.

For that reason, I am with the divide in the fall group! Yes, you will most certainly damage some leaves, and it may seem as though the plant suffered a setback, but in the next season they will “spring back” to put you in awe of the project which you completed.

Here is what you will need to get started:

  • A wheelbarrow, shovel, cutting tool, some organic matter, and water. Start out by assessing which plants need to be divided, then decide where you will plant them. Keep in mind that hosta leaves will scorch in full sun, so be sure to select an area that gets only a few hours of morning sun.
  • Next, dig around and below the hosta being careful not to damage too much of the root system. Lift the entire plant out of the ground and don’t be shy about asking for help if it is too heavy. With a garden hose, rinse as much of the soil from the root system.
  • Now is the time to get tuff. You can take your shovel or cutting tool, and slice all the way through the roots, and divide the plant into one or more sections. If the roots are not too tangled, it is best to pull the sections apart by working with your hands.
  • Next, add the organic matter or compost in the hole and replant one of the sections where you just dug it up. Place the other sections in your wheelbarrow and take to the area you will plant. Dig holes at least twice the size of your root system. Again, add organic matter or compost to the hole, and fill in around the plant.
  • Be sure to water all generously and regularly.Hosta33Another tip when planting is to either plant a “specimen” or in groups of 3 or 5 for an attractive look. If you have room, consider adding some companion plants such as Astilbe, Baptisia, Bleeding heart, Dianthus, or Pulmonaria (lungwort.)Above all, be patient. The hosta may not look very attractive at this time, but after it has had a long winters nap it will emerge in the spring looking as beautiful as ever!

A Geranium by any other name…


by OCMGA Master Gardener Vicki Schilleman


Geranium ‘Brookside Blue’

When you hear ‘geranium’, I’m guessing you picture the beautiful annuals that are so beloved by northern gardeners. While I, too, love those gorgeous full heads of color all summer long, there is another geranium that I love as much: the ‘hardy geranium’.

Hardy geraniums are distant cousins of the tender plants known as geraniums. The irony is that the hardy plants have technical rights to the name (they belong to the genus Geranium), but it is the tender ones that most people think of when they hear “geranium”.

Technically, the familiar houseplants are not geraniums. They belong to the genus Pelargonium. But the confusion is natural. Both the hardy and tender versions belong to the Geraniaceae family, and they both used to be in the genus Geranium. Then the tender ones got split off into Pelargonium, but people kept right on calling them geraniums.

Pelargoniums were brought to Europe from South Africa early in the seventeenth century. They found immediate favor, but it was their scented leaves and not their flowers that caused the sensation. By the time they came to the U.S., more than a century later, Pelargoniums’ large clusters of bright red, orange, or hot pink flowers had taken center stage, a position they still hold; scented-leaved geranium fans are passionate, but a minority.


My Cranesbill: ‘Bikova’ clustered at the base of a tree peony

Meanwhile, back in the temperate British and American countrysides, numerous species of native Geranium, known to the populace as cranesbills, were finding their way into gardens. The cranesbills do double-duty, offering beautiful, long-lasting leaves as well as loose umbels of flowers in a wide range of pinks, blues, and purples.

You can usually tell these plants apart by general appearance: the leaves of Pelargonium are thicker than those of true Geranium, their flower stems are stiffer, and though individual flowers are smaller, they tend to be clustered more densely. And if you look closely at the individual flowers, you can usually see a tiny spur on the pelargonium flower stalk (geranium flowers don’t have them).


Cranesbill ‘Bikova’ in bloom

Color helps too: although both kinds might be white, plants in the genus Geranium come in purples, blues, and blue-tinged reds and pinks; those in Pelargonium may be true red, orange-red, pink, or orange, but they do not sing the blues.

Note: Wild geranium, also known as cranesbill,  (Geranium maculatum) is a hardy perennial excellent for naturalizing, or filling in, under bushes or wherever there is dappled shade or part sun. The American native wildflower, with it’s flat, delicate-looking pink-lavender flowers and deeply notched foliage, is very easy to grow, ultimately reaching between 12 and 18 inches.

The Scent of Improved Health

The following article is taken from “Renew”, a UnitedHealthcare magazine. The source quoted is The National Association for Holistic Aromatherapy.

Chamomile: relieves anxiety; promotes sleep; is anti-inflammatory

For thousands of years, the medicinal benefits of

Lemon: energizes and uplifts the mind; detoxifies; repels viruses

inhaling aromas of certain essential oils have been known by many cultures around the world.

Today, aromatherapy — using plant extracts and essential oils for their scent — is used in some hospitals and clinics as complementary medicine.

Eucalyptus: relieves congestion; clears and energizes the mind; helps with brochitis

A 2013 study published by Bentham Science in Current Drug Targets has indicated certain health benefits of aromatherapy — from killing bacteria to improving mood disorders to combating insomnia. In 2014, a review of several studies published

in the Journal of Alternative and Complementary Medicine found a positive effect from essential oils on sleep disturbances with no adverse reactions. Plus, for more than a decade, essential oils have been studied for use in cancer therapy (in tandem with conventional treatment), and the results of more than 100 studies have been promising to doctors and other health practitioners.

Lavender: reduces anxiety; produces a sense of calm; promotes cell regeneration (which is good for wounds and burns)

What’s wonderful about aromatherapy is that you can experience it at home. Essential oils are widely available for purchase, so check you local grocery or health foods store. The National Association for Holistic Aromatherapy, naha.org, also has tips to get you started.

Here are a few ways to use aromatherapy essential

Peppermint: relieves nausea; is an analgesic for aches and pains; reduces migraines; energizing

oils at home:

  • Dilute into a spritzer and spray a room
  • Add drops to your bath water
  • Add drops into boiling water or a steamer

Bulb Farmers Rock!

OCMGA Master Gardener David Calle is passionate about gardens — especially historic gardens and finding a way to incorporate lessons from the past into our own gardens.

From David’s blog explaining the passion behind his blog:  “I created this blog to share my love of gardens and the stories and people behind them.  My passion for historic gardens has taken me to dozens of gardens across 5 continents.  I hope you will join me on this journey and share your comments and experiences.”

I’m crazy about his stories and one of his recent ones “Bulb Farmers Rock” really captured my fancy because, on my bucket list, is a trip to Keukenhof when the bulb fields are all in bloom.

Take a minute to enjoy David’s blog post, and subscribe so you won’t miss future blogs!


Little Scientists at Work

by OCMGA Master Gardener Shirley Martin

As part of the preparation for the upcoming planting season several Master Gardner volunteers went to some classrooms at the Appleton Bilingual School and presented a seed starting class. These children and their teachers were very interested in the project and took the instructions very seriously. They are documenting their results with words and pictures. They were so excited to see the seeds sprout in the “planters” made from old water bottles.

The bottles are cut in half and the top is inverted into the bottom. A coffee filter is stuffed into the neck of the bottle then the top of the bottle is filled with soil and seeds are planted in it. This coffee filter acts as a “water wick” to transfer water from the bottom of the bottle (reservoir) to the the planting medium. It is inexpensive and effective. It fits on most windowsills and is an ideal mini-planter.

Rhubarb Season is here

by OCMGA Master Gardener Tom Wentzel

UntitledThis is my first rhubarb harvest this year. There was one more, but I ate it. We all have bunches of recipes for using rhubarb so I won’t go there.

Chinese records from 2700 BC record its medicinal use. Marco Polo documented its use, but I’m not sure if he introduced it to Europe. A while ago, I visited Old World Wisconsin. In one of the Germany heritage houses there was a string of, what I thought, were chicken bones. It was dried rhubarb! Many of the historical uses that I have read seem to be medicinal, rather that culinary.

My first picking didn’t have that lip puckering sourness of later season harvests. The sourness is due to the pH (acidity) which is in the range of 3.1 – 3.2. For reference, fresh lemon juice has a pH of about 2. Adding sugar doesn’t “neutralize” the acidity, it simply covers it up.

Rhubarb leaves have a reputation as being toxic. This is due to the relatively high concentration of oxalic acid. Oxalic acid’s primary effects can be stomach irritation and kidney problems. Ten pounds of leaves would be required to deliver a lethal dose. Kitchen pot cleaners such as Bar Keepers Friend and ZUD use oxalic acid as the primary active ingredient.

Uses for Rhubarb leaves:

  • Use them as a mulch.
  • They can be composted in limited quantities.
  • GREAT for leaf castings
  • I have seen recipes for rhubarb leaf concoctions as insecticides and repellents. These have been anecdotal, their effectiveness has not been verified.

I will break my promise not to talk recipes. Here’s mine: Peel, then eat.