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Historically, fruit trees, shrubs, and berries were grown at home out of necessity. Colonialists were entirely dependent on what they could produce themselves, and in time, a fruitful garden became a common symbol of independence from foreign imports—highlighting a new American pride in agriculture.

The farm-to-table movement of today epitomizes the fruit-growing traditions of the past by “growing as close to the plate as possible.” Sweet, juicy fruit can be easily grown in gardens of all sizes: on small urban lots, in containers on terraces, or in large suburban gardens. Harvesting homegrown fruit continues to be a gardener’s most satisfying pleasure, and with a bit of advance planning, choosing suitable varieties to plant this spring is possible. Here are a few ideas to get you started creating, and/or caring for, your edible landscape.

PHOTO: A hanging basket growing a mix of strawberry cultivars and lettuces.

Day neutral strawberries are grown in our vertical wall and hanging baskets in the Regenstein Fruit &  Vegetable Garden.

Plan to plant strawberries

No grocery store strawberry ever tastes as good as one grown in your own yard. An easy starter crop, strawberries are self-fertile, so you can start small if you like—plant just one variety or only one plant—and still reap a reward. Choose strawberry varieties carefully, however—they vary greatly in flavor, disease-resistance, tolerance of different climates, and harvest time.

Good choices for Illinois gardens are larger June-bearing strawberries such as ‘Earliglow’ and ‘Allstar’. Day-neutral or everbearing strawberries were developed to produce flowers and fruit continuously throughout summer and fall, ignoring the seasonal effects of day length on fruit production. Of the many day-neutral and everbearing varieties to choose from, ‘Tristar’ is a reliable berry for our zone. At the Garden, we grow everbearing strawberries ‘Mara de Bois’ and ‘Seascape’ in hanging baskets and vertical plantings, because they are among the first to fruit in the spring, but also produce a June crop followed by a final fall crop.

Planting several varieties together in your garden extends your harvest time, ensuring there are plenty of strawberries for eating out of hand and enough fresh berries left over to make strawberry jam.  

Choose healthy plants for a healthy harvest

Start with quality, virus-free, and disease-resistant plants. Mail order nurseries and garden centers have bundles of bare-root plants available. Lesser quality plants are prone to fruit rot, mold, and fungal diseases like Verticillium wilt.

PHOTO: Glass cloche cover strawberry plants in a garden plot in early spring.

Strawberry flowers are susceptible to frost. Here, a transparent plant cover called a cloche (from the French word for bell) is used to protect plants if frost is expected.

Select a planting location in full sun; avoid low-lying spots or crop beds that have grown tomatoes, potatoes, or cane fruit in prior years. These crops can harbor soil pathogens like Verticillium and Phytophthora which can affect new plantings. While strawberries prefer to grow in soil with a bit of acidity, a pH of 6.2 is ideal; the varieties mentioned above perform well in Chicago.

Aim for early spring planting, as soon as the soil can be worked, and its temperature is above 40 degrees Fahrenheit. Mid-April to mid-May is ideal. Space plants 12 inches apart, leaving 3 feet between rows. Fifty plants produce enough fresh home-grown fruit for four people all summer long.

Plant with midpoint of crown at soil level. Roots should be planted straight down. Strawberries are shallow-rooted, and mother plants spread by runners—which can be removed if desired, to develop stronger plants and to promote bigger fruit.

Water your plants well, particularly when they are fruiting. Mulching with straw helps keep fruit clean and dry, and up off the soil.

Spring tasks: Prune Raspberries

Red, yellow, black, or purple raspberries are easy to grow in hedgerows as natural barriers along lot lines or on post-and-wire trellises. Cane fruit is best managed with proper spring pruning, which prevents a tangled mess and makes your late-summer harvest far easier. Regular pruning keeps brambles in line while allowing air flow through the plant—lessening the risk of fungal diseases like Botrytis and rust, and increasing both yield and berry quality. Both types of raspberries—summer-bearing and everbearing (or fall raspberry)—benefit from a good March pruning.

PHOTO: Different kinds of berries in baskets, lined up in a grid.

A bountiful berry harvest on its way to our Farmers’ Market? A bountiful home harvest is also possible with vigilant pruning.

Summer-bearing raspberries produce a single crop in the summer on canes which have overwintered. It is important to confine them to a 1- to 2-foot-wide hedgerow to encourage air flow and sunlight. Begin your pruning by removing dead, diseased, or damaged canes first. Then, head back (prune) the spindly top 6 inches of cane tips. Removing the thinnest wood which produces the smallest berries forces the growth into the more vigorous lower part of the plant.  Finally, remove less vigorous canes—in an established plant, those canes with less than a pencil’s diameter thickness—leaving 6 inches between canes (enough room to easily pass your hand between canes).

Fall-bearing red and yellow raspberries can produce fruit on both the current season canes (called primocanes) and second-season growth (floricanes). Thus, they can be pruned to bear one or two crops with a method called, “double cropping.” (We demonstrated both methods last year on our brambles in the Regenstein Fruit &  Vegetable Garden.)

  1. To produce one heavy fall crop, cut all autumn raspberry canes back to ground level in the spring. Canes should be cut as close to the ground as possible to encourage new buds to break just below the surface. All new canes will grow from this radical pruning and produce a single crop of berries.
  2. A second method of pruning produces a small crop on the previous year’s growth and later, a second crop on the current season’s canes. When a double crop is desired, remove dead, diseased, or damaged canes in March, leaving the vigorous canes to fruit. Tip-prune those back by one-third of the total length of the cane, or to trellis height. The new shoots or primacies will produce the second larger crop. After the second fruiting, the canes will die and should be removed.

Pruning for blackberries is similar to raspberries. They are also pruned in March by heading back the “leaders”—the main canes—by one-third (or about 36 inches). This tip-pruning helps to stimulate the growth of lateral branches, which is where blackberry sets fruit. The lateral branches should be pruned back to 12 inches, or where the branches’ thickness is about the diameter of a pencil. 

Want to learn more about cultivating berries? Join us for Growing Fruit Trees and Berries, May 29 to July 10, or check out other fruit cultivation classes at the Garden this spring.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Time to Uncover the Rose Garden

Give the roses their breath of fresh air!

Tom Soulsby —  April 10, 2013 — 3 Comments

Who doesn’t love a warm winter blanket? With unseasonably cold temperatures continuing into early April, that blanket has been especially welcome this year. If you are like me, though, you just can’t wait for that first day when you lose the covers and open the windows. It is that breath of fresh air that tells us summer is just around the corner.

PHOTO: A view of the roses near the education building.

Roses under a warm winter blanket of mulch.

Our Krasberg Rose Garden is ready for its breath of fresh air, too. All winter, many of our roses have been under their warm blanket of composted horse manure. Compost protects roses from the harsh winter winds and freeze and thaw cycles that can be deadly to many cultivars.

As the hours of sunlight increase and daytime temperatures get warmer, however, we need to start inspecting our roses for signs that it is time to remove the compost and prepare the roses for the beauty yet to come.

The process is fairly straightforward. In late March, or whenever we have had several warm days with limited risk of a killing frost, we use our hands to carefully remove the thawed compost from around a rose bush. We need to inspect several bushes because some areas of our Garden thaw and start actively growing earlier than others.

PHOTO: A rose with new spring growth.

New growth from the base of the plant.

We look for yellow, bright green or reddish growth around the base of the plant — these are new rose canes. If we do not see any new growth or if new growth is still very small, we may cover the roses for a few more days. The warm compost encourages rose bushes to break dormancy.

However, if we see new growth and it is an inch or longer, then is it time to completely remove the compost and let the canes grow freely. The sooner this new growth begins to photosynthesize in the sun, the healthier and stronger your plant will be the rest of season. Remember that this new growth is very fragile, so we use gentle care when removing the compost.

PHOTO: Rose before Pruning

Look for black canes that indicate they are dead.

Once we remove the compost, our team then prunes the canes for optimum health. We first remove any cane that is black or brown — these are dead or dying — and anything that looks diseased.

From there, we prune the shrub until it has five or six healthy, large canes that are at least the diameter of a pencil. The pruning should result in an open center, with the top bud on each remaining cane facing away from the center of the plant. The open center maximizes the amount of sunshine and air circulation within the plant — important components to plant growth and disease prevention.

We also take time to frequently disinfect our pruning tools as we work through this late-winter chore. Tools can easily transfer diseases from one rose shrub to another, so sanitation is very important. Mix a solution of 10 percent rubbing alcohol or bleach and 90 percent water in a spray bottle to spray on your tools.

PHOTO: The final rose after spring pruning.

After pruning, the remaining canes look healthy.

By taking a few simple steps like these right now, the rose bushes will be on their way to beautiful blooms in June. Now that’s a breath of fresh air.

You can learn more about rose care with a class at the Joseph Regenstein, Jr. School of the Chicago Botanic Garden. Click here to see what classes are currently available.


©2013 Chicago Botanic Garden and my.chicagobotanic.org

Journey to Kokufu

The Garden's Curator of Bonsai and Newest Bonsai Book Travel to Japan

Karen Z. —  April 4, 2013 — Leave a comment
KANJI TEXT: To Garden is to Learn.

Niwa ni manabu koto desu.
To garden is to learn.

PHOTO: Overhead shot of viewing room.

The main gallery at Kokufu.

That’s why Ivan Watters, the Chicago Botanic Garden’s curator of bonsai, travels to Japan every year to attend Kokufu — the Japan National Bonsai Exhibition and most important bonsai show in the world.

“It’s a true learning experience,” he says. “You pick up technical ideas, artistic ideas, and learn a few bonsai tricks.” For example? “The first branch of an informal upright bonsai should come out of the midline across the front of the trunk. But the unconventional branch on one entry started at the back of the trunk and wrapped around to the side, with a secondary branch positioned to hide the manipulation.” It’s a vivid description, sure to be shared with his bonsai volunteers.

PHOTO: Ivan Watters

Bonsai curator Ivan Watters arranges a speciment at a photo shoot for Bonsai: A Patient Art.

Watters is a long-time member of the Nippon Bonsai Association, the venerable group that sponsors the exhibit. Held this year (for the 87th time) at the recently renovated Tokyo Metropolitan Art Museum, Kokufu brought together 204 of the most outstanding trees in the country, culled from 500 entries. As always, requirements for entry are firm. Trees must reside in Japan (quarantine issues prohibit the Garden from competing) and, if selected, entrants must wait three years to compete again in the show.

This year marked Watters’ 20th year attending the show. What caught his eye this year? One large bonsai that combined nine separate Japanese white pines, each more than 100 years old. “It was the majesty of it,” he remarks, “so beautifully placed in their container.” Also large in scale were several bonsai from the Imperial Palace Collection, holding pride of place at the entrance to the show. Displayed on burgundy velvet cloths, the imperial bonsai befit the proportions of the Imperial Palace — many imperial trees are more than 500 years old and have been in the collection for more than 300 years.

Watters took a side trip to the Omiya Bonsai Art Museum in Saitama, and to a small exhibit (just eight trees) at a temple celebrating ume season, the flowering of Japan’s plum or apricot trees.

PHOTO: Susumu Nakamura trains a bonsai.

Bonsai master Susumu Nakamura tends a white pine that he donated to the Garden.

The trip wasn’t all business. Watters also hosted an 81st birthday party for bonsai master Susumu Nakamura at the latter’s favorite eel restaurant, Izuei. Nakamura, the former vice chairman of Kokufu, donated 19 of his trees to the Garden’s collection in 2000. (Only one other donated tree has come to America, at the United States Botanic Garden.) On this latest trip to Japan, Watters gifted Nakamura with a copy of the Garden’s newest publication, Bonsai: A Patient Art. The beautifully photographed book illuminates the intricacies of bonsai in both art and history. Most of the trees that came from Nakamura are included in its pages, including an extremely fine example of a formal upright bonsai, the white pine shown here, which has been trained for at least 100 years.  

This spring, Watters and his volunteers are busy repotting more than 100 bonsai trees in preparation for the reopening of the bonsai courtyards on April 29. Watters is also teaching bonsai workshops. Bonsai Basics on June 1 is a good first class to begin your learning.

PHOTO: Bonsai Book

Curious about the Japanese trees at the heart of the Garden’s bonsai collection? Bonsai: A Patient Art is available to purchase. This stunning volume presents more than sixty living masterpieces from the Garden’s collection. Board member and bonsai enthusiast Robert H. Malott supported publication of this beautiful book.


©2013 Chicago Botanic Garden and my.chicagobotanic.org

Willow Pruning in the Malott Japanese Garden

Walking on Water

Mike Kwiatek —  February 8, 2013 — 2 Comments

If you took advantage of the warm weather last Tuesday and decided to visit the Chicago Botanic Garden, you may have noticed something unusual, especially if you wandered over to the Elizabeth Hubert Malott Japanese Garden.

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The Zigzag Bridge was closed for public safety until we could finish pruning.

The sight of horticulturists walking on water was not a hallucination.
In spite of the 60-degree weather, the lake was still frozen and we took advantage of the situation to finish some winter pruning.

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The arborists, equipped with the proper safety equipment, are busy pruning the small willow branches.

 Though this willow pruning appears very intense, even harsh, it provides airflow into the tree and gives young branches more room to grow. Some of the large, more upright branches are left to provide height. From an aesthetic point of view, this pruning gives the tree significantly more texture, creating clumps that flow into thin weeping branches. As willows can become quite large, pruning also prevents the tree from becoming disproportionately so.

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Benjamin Carroll stands on the ice to prune and provide direction to the arborists.

For the past four years, Benjamin Carroll, the senior horticulturist who maintains the Japanese Garden, has been working with arborists from the area to shape up his trees to give them a more traditional appearance. This style first emerged in Japan.

Seba on the Kisokaido by Utagawa Hiroshige shows the style we are trying to emulate.

Before this style of pruning was implemented, the willows were pruned to appear mounded. For the first three years of this pruning style, many large branches were cut to drastically change the appearance of the trees. This past year we were able to focus on smaller branches.

A willow prior to pruning this year.

A willow looks different before it was pruned this year.

January is the best time for us to do this because the trees are dormant and the sheet of ice on the lake is fairly thick. Tree dormancy is very important when pruning because nutrient flow is minimal and the wounds made by winter pruning will heal quickly in the spring.

Cleanliness is very important to us, it looks good and reduces debris that could promote disease.

While the arborists cut branches with pole saws and chainsaws, I moved branches off the ice.

 The thickness of the ice is also helpful to us because it simplifies cleanup.

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After the branches are moved to shore, they’re loaded onto a club car and taken to the mulch pile.

Cleanliness is very important to us because it not only keeps the Garden looking its best but it also reduces debris that could cause disease problems in the future.

Though we look fairly confident walking on the ice, it is important to remember that ice is always dangerous. We always have seasoned professionals and the proper safety equipment nearby.


©2013 Chicago Botanic Garden and my.chicagobotanic.org

Goodnight, Roses

Karen Z. —  December 13, 2012 — 1 Comment

What a difference a month makes!

In early November, many of the roses that bloom twice per year (called remontant, or repeat-blooming) were still putting on quite a show in the Rose Garden. Even that late in the season, the garden looked exceptionally lush—canes were tall, bloom was heavy, and November’s cold-but-not-freezing nights kept the last of the season’s flowers going through Thanksgiving.

Finally, early December brought below-freezing nighttime temperatures—and Garden staff jumped into action to put the rose beds “to sleep” for the winter. Now the garden looks entirely different.

  • View 1: The Rose Garden in fall View 1: The Rose Garden in fall
  • View 1: The Rose Garden in winter View 1: The Rose Garden in winter
  • View 2: The Rose Garden in fall View 2: The Rose Garden in fall
  • View 2: The Rose Garden in winter View 2: The Rose Garden in winter
  • View 3: The Rose Garden in fall View 3: The Rose Garden in fall
  • View 3: The Rose Garden in winter View 3: The Rose Garden in winter
  • View 4: The Rose Garden in fall View 4: The Rose Garden in fall
  • View 4: The Rose Garden in winter View 4: The Rose Garden in winter
     

 

The process that our staff uses to prep roses for winter is the same process you can use in your rose garden, too.

Step 1: Prune canes.

While early spring is the major pruning season for roses, end-of-the-year pruning protects the plant from winter wind (canes can whip around and scar each other, and stiff winds can pull long-caned plants out of the ground). Prune out thin or crossing canes to open up the plant, and cut back remaining canes by one-third in height.

Step 2: Clean up leaf litter.

This simple step can prevent major problems later, as leaf litter is a prime source of diseases and pest problems. As you can imagine, we have a lot of leaf litter in a garden with 5,000 roses plants; our truly dedicated volunteers and staff spent two days removing every last leaf from the beds.

Step 3: Mulch.

Mounded up and around each rose plant is a thick layer of mulch (we use well-aged horse manure, but chopped and well-composted leaves work, too). Mulch protects the plants, helps maintain even temperatures, and adds fresh nutrients to the soil. When spring arrives, this extra blanket of mulch will be removed.

And speaking of spring, check out our YouTube video on how to prune climbing roses:

©2012 Chicago Botanic Garden and my.chicagobotanic.org