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Make your garden irresistible to birds

Posted in Chicago Botanic Garden, Chicago Tribune, Going green, Letters to the Editor, Topics Of Interest on April 5, 2026| Leave a Comment »

A goldfinch feeding on coneflowers. (RJ Carlson/Chicago Botanic Garden)

By Tim Johnson | For the Chicago Tribune

I have developed an interest in bird-watching and would like some advice on how to attract more birds to my garden. 

— Maria Alvarez, Grayslake

I was also motivated to start bird-watching after a fun vacation sighting of a pink flamingo on St. John, U.S. Virgin Islands, last December. Another highlight this winter was seeing eight mourning doves feeding on the ground outside my home at one time. Winter is a good time to plan to enhance your garden with plants that will attract birds all year long. It takes more than feeders, birdhouses and a bird bath, along with some flowers for a truly bird-friendly garden. Birds need a complete habitat that includes food, shelter, nesting areas and perching spots. A good garden for birds tends to have more of a natural look. Design your garden so that there are different vertical levels, each attracting and providing something important to different bird species. Some birds prefer the canopy of tall trees, while other birds perch in the understory trees and shrubs. Different species of birds have varying requirements and preferences for nesting, eating and shelter. Try to create as many of these levels as possible in your backyard garden to attract a larger variety of birds. Birds use a stand of hemlocks in my garden for shelter while using the feeders. Even open areas of soil can be beneficial by providing an area for birds to take a dust bath.

Select plants to provide food for birds at different times of year. Fruits of different plants ripen in different seasons. For example, serviceberries provide spring-ripening fruit, red-twig dogwoods provide summer fruit, while hawthorns and crabapples provide fruit in fall and winter. I just replaced some invasive Callery pear trees with serviceberries in my garden. Perennials such as purple coneflower and grasses such as a prairie dropseed provide seed for a food source. Sunflowers are quick-growing annual flowers that produce seeds that are attractive to birds. Nectar-producing plants such as penstemon, bee balm, and columbine appeal to hummingbirds. Include a mix of evergreens in your planting to provide year-round shelter for birds. When feasible, leave some dead branches on living trees to provide something for the birds to perch on. Prune any dead branches that are safety hazards though.

Leave the leaf litter in your garden beds next fall as an easy and environmentally friendly method to recycle material and help meet some of a bird’s basic needs. Other organic materials such as small twigs, fallen seeds, fruits and berries should be left in the litter too. Many insects thrive in leaf litter and insect-eating birds will be attracted.

There are many kinds of seeds and feeders to choose from if you decide to start a feeding program. Squirrels can be a nuisance and eat more seed than birds do, so choose a squirrel-resistant feeder. We have had good luck with a cylindrical, squirrel-resistant feeder. Take time to research options, as different species of birds prefer different types of seeds and feeders, and no one type is preferred by all birds. Avoid buying bags of mixed birdseed as they tend to contain a lot of filler such as red millet, which most birds won’t eat. The filler ends up on the ground where it rots. Place your feeder in an open area where it is easy to see, 10 feet or so away from protective cover and convenient to refill. If feeders are too close to large plants, squirrels will have easy access to them. Be consistent feeding birds and they will become accustomed to your feeder. Stamp the snow down under the feeder to accommodate ground-feeding birds such as doves and dark-eyed juncos. To maximize the number of species that visit your feeders, offer a variety of food at different heights above ground.

Black oil sunflower seeds attract a wide variety of birds including cardinals, woodpeckers, blue jays, goldfinches, purple finches, chickadees, titmice, and nuthatches. Safflower seeds also attract a wide variety of birds, with the advantage that squirrels, blue jays, starlings, and grackles do not like this seed. Nyjer is a good seed to attract goldfinches. Nyjer is a very small, black seed best used in a feeder designed for it, which can be hung close to a viewing window under an eave. White millet seed can be spread on the ground to attract ground-feeding birds. Suet is another option for feeding birds. Suet is rendered animal fat that is usually mixed with seeds and dried fruit and sold in small cakes. It is best to place it in a cool, shaded area in amounts that the birds can eat in a few days to keep it from spoiling, so it works well for winter feeding.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden. 

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Now is the perfect time to prune your garden

Posted in Chicago Botanic Garden, Topics Of Interest on March 8, 2026| 1 Comment »

A small folding hand saw is best for removing large stems at ground level. (RJ Carlson/Chicago Botanic Garden)

By Tim Johnson | For the Chicago Tribune

Pruning is my favorite gardening task by far. I prune plants that have gotten overgrown very aggressively, and I suspect that will be the best approach for you, too. Most gardeners are hesitant to prune hard enough to get good results. Overgrown plants have little value in your garden, so if they do not respond well to pruning, you will have an opportunity to add new plants to replace them. The dormant season is the best time of year to do this work, as healthy plants will respond with lots of new growth. I generally start this rejuvenation pruning in the middle of February and finish it before the shrubs start to grow in the spring. This date varies from year to year depending on the weather.

First, identify the shrubs in your garden to better understand how they might respond. Here are some general guidelines that should work for most shrubs. Start by removing large stems at ground level, especially if they have formed mature bark. A small folding hand saw is best for this task, and it will minimize damage to any remaining young stems. It is best to prune at ground level to avoid leaving stubs (which I often see in pruned shrubs). The remaining young stems will need to be cut back if they are spindly and flopping over. It is difficult to give exact height recommendations without seeing a picture of your shrubs, but you will probably end up cutting the remaining stems back to a height of 2 to 3 feet. Make the cuts at an angle 1/4 inch above a bud or side branch when possible. The goal is to encourage growth from the base of the plant, so err on the side of cutting the shrubs back lower than you think they should be. If you do not cut them back hard enough, you will end up with spindly growth rather than with a shrub that is densely branched from the base. This type of pruning is dramatic.

If your shrubs do not have young stems to work with, cut back the thick old stems to about 2 feet, just above the point where there is a young stem. This results in an ugly shrub, but there will be new growth from the old stems and base in most situations. There have been very few occurrences in which I did not get good results from this pruning approach. Since the goal is to remove most of the old stems, prune back thick remaining stems to new canes that develop lower on the stem over the next couple of years. Cut back to shorten any young stems that remain. Once you get these thick old stems to a couple of inches from the ground, you should be able to stop cutting them back, providing you have developed a good-looking shrub.

It’s OK to be much less aggressive when pruning most evergreen shrubs, trying not to cut beyond green foliage. Spreading yews respond to drastic pruning that goes into woody stems with no leaves, but they can be very slow to fill back in. The more aggressive the pruning, the longer it will take for yews to look good again. Plan on at least two to three years for yews to recover. Replacing severely overgrown yews may be the best strategy. Arborvitaes do not respond well to aggressive pruning.

Monitor these shrubs in spring and cut out any dead portions of stems. It is likely that you will have some follow-up pruning to do. Cut back any new growth that is shooting around the other stems to encourage the shrub to develop more densely. Spring-flowering shrubs like lilacs and viburnums that formed flower beds the previous year will not flower until next year. It may also be beneficial to fertilize your shrubs in spring and provide extra water during dry spells throughout the growing season.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden. 

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Can I leave leaves in my garden beds?

Posted in Chicago Botanic Garden, Going green, Topics Of Interest on November 9, 2025| Leave a Comment »

Oak leaves on a lawn. | RJ Carlson /Chicago Botanic Garden

By Tim Johnson | Published in the Chicago Tribune

Will it be okay if I leave leaves in my garden beds at home? My work schedule is heavy this fall and I need some time to relax on weekends versus spending hours picking up leaves.

— Alfredo Alvarez, Highwood

My time for gardening at home is very limited, too, so I look for ways to make my gardening time more efficient. I also prefer a more natural look to my garden, which, fortunately, is easier to maintain, so I adjust my maintenance routines accordingly.

Leaves are now falling and starting to pile up in my garden. The usual fall routine for many gardeners is to remove all the leaves and either bag them up or pile them at the curb for transportation to a landscape waste facility, where they are turned into compost. I have left leaves in my garden beds at home for more than 25 years with good results, which saves time on cleanup while benefiting the environment. This also saves money and time as I do not have to purchase mulch for my garden beds. The only exception is when I plant in the fall, in which case I add mulch to help the new plants through their first winter.

In addition, I do not cut back perennials in fall but wait until spring to trim them to about six inches above the ground. The fallen leaves create a natural mulch, which helps suppress weeds and improves the soil with organic matter as they decompose. The perennial foliage and fallen leaves in the beds create a natural look with lots of winter interest, as well as habitat for insects and wildlife. We all need to do more to support pollinators, and we can help by leaving perennial foliage standing through the winter and keeping leaves in our garden beds year-round. Cut perennials back in late spring to six to eight inches above the ground for maximum benefit for insects.

There are several mature oak trees in my garden, so the leaves tend to pile up too deeply here and there in the borders or blow into dense piles that must be reduced to avoid smothering perennials, groundcovers, and bulbs. Excess leaves can be piled in a corner to decompose, creating compost to use for future soil improvement. Removing leaves from the edges of your garden beds will give you a clean boundary between the lawn and the beds, adding a sense of order to the garden’s appearance. You do not need to grind them up to use as mulch — simply let them fall and blow into the beds naturally.

You can use a mulching mower on the lawn to mulch the leaves and grass clippings to save time while returning nutrients to the lawn. I prefer the look of some leaves left on the lawn in fall versus a clean look and have lowered my mower cutting height to about 2 inches. Change the direction of mowing each time you mow. You should be able to easily see the blades of grass after you are finished mowing for the season. A thick layer of leaves covering the grass will likely smother the lawn if left on it over the winter. A medium to dense layer of leaves can damage any areas of the lawn that have been seeded earlier in the fall and are just getting established. You will need to carefully rake or blow some of the leaves off the new grass if the ground is too soft to push a mower over. If the mower leaves ruts as you are mowing, then the area should not be mowed.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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Don’t let deer destroy your garden

Posted in Chicago Botanic Garden, Chicago Tribune, Topics Of Interest on October 11, 2025| Leave a Comment »

Surround a small tree with a 6-foot-tall barrier of hardware wire mesh supported by fence posts. | RJ Carlson/Chicago Botanic Garden

By Tim Johnson | Published in the Chicago Tribune

I just moved from Arizona to this area, and a neighbor advised me that deer were a problem in the neighborhood and that I need to protect my plants from them. What does this mean?

— Sasha Black, Northbrook

Deer can do a lot of damage to area gardens from feeding during the growing season and rubbing trunks in the fall. I live in Highland Park with a fenced backyard, and I had a significant buck rub on a clump-form serviceberry about four years ago. If your home is near a forest preserve or other open green space, your chances of having issues with deer will be greater. Try spraying a repellent on any plants you observe being browsed during the growing season. Any damage you see may also be caused by rabbits, which have been a significant problem for many gardeners this year. I have seen several perennial gardens completely eaten by rabbits this summer. This can be incredibly frustrating for anyone tending a garden.

Garden staff has begun installing tree protection for deer rubs, and we recommend you do the same if you have any young, smooth-barked trees. Bucks can cause significant damage to young trees in the fall by rubbing their antlers on trunks. Male deer do this to clean their antlers of summer velvet from early September through November while also marking their territory during the breeding season. The first week of September is a good time to install deer protection. Bucks may repeatedly strike trees for the noise effect, showing dominance and intimidating other bucks. They coat the twigs and bark with scent from glands in their faces and underbodies to mark their territory. Trees that are 1 to 12 inches in diameter with smooth bark — like maples, lindens, birches, and magnolias — are most likely to be damaged by deer rubs. Larger trees with smooth bark as well as clump-form trees can also be damaged. Unfortunately, buck territories currently include many home gardens with young trees.

The damage to trees from buck rubs comes from the shredding of bark from a foot or so above the ground up to 3 to 5 feet up the trunk. Young trees have very thin bark that offers no protection from such damage. Usually, the damage is done over a 24-hour period. The tree’s vascular system — which is just below the bark and transports water, nutrients and food between the roots and leaves — gets damaged and the underlying wood is exposed. If rubbed all the way around, the trunk can be effectively girdled, which can lead to the eventual death of the tree in one to three years. If the damage is mostly located vertically on the trunk and does not go all around the trunk, the tree can survive, although it may die on the side where the damage occurred.

Protect the trunks of your trees from the ground to about 6 feet up the trunk. Wrapping with burlap or paper tree wrap does not provide enough protection for deer rubs, but it can provide some protection from rodents feeding on the lower trunk in the winter. Try wrapping your tree trunks with a sturdy wire mesh available at hardware stores. Use zip ties to secure the wire mesh around the trunk of the tree. Chicken wire usually works too, although I have heard about nearby gardens where aggressive deer tore chicken wire off the tree and left significant damage to the bark. There are plastic tree wraps that should also work. Surround a small tree with a 6-foot-tall barrier of hardware wire mesh supported by fence posts if you are unable to wrap the trunk. Deer repellant is not usually effective in controlling buck rubs. You need to get a sturdy physical barrier around the trunks of your trees to prevent damage from buck rubs.

Trees can heal after a surprisingly large amount of damage. Trim off any loose, shredded bark where it’s not connected tightly to the trunk. If possible, cut the wounds into an elliptical or football shape to help the tree recover more quickly, but do not dramatically enlarge the wound to do this. There is no need to use wound dressing or to wrap the damage. Smooth edges heal better than the ragged edges left from the deer rubbing. Prune back broken branches as needed. Small clump-form trees can be ruined if too many branches are broken.
Deer will browse yews and arborvitae, so you may need to protect these plants up to about 6 feet too, as deer can ruin them over the course of winter. Chicken wire or a plastic garden netting works for this, and the netting is usually easier to apply.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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Should I wait until next spring to plant?

Posted in Chicago Botanic Garden, Going green, Topics Of Interest on August 24, 2025| Leave a Comment »

Proper watering of plants before and after planting is critical during the hot summer season. | RJ Carlson/Chicago Botanic Garden

By Tim Johnson | Posted in the Chicago Tribune

Spring got away from me this year, and I missed out on installing a large new garden in my backyard. A friend gave me the impression that I should wait until next spring to do the planting. Do you think that was good advice? I suspect there is still plenty of hot weather to come and wonder how a new planting will fare if I go ahead and plant now.

— Hal Peterman, Elgin

I think it is fine to continue planting all summer long and do so myself. My springs tend to be very busy, so I often do not get around to planting until mid- to late summer. Some gardeners agree with your friend that planting is best done in the spring and fall. But in my opinion, there is no reason to stop planting during the summer. In fact, I have always had good results with my summer plantings.

Chicago Botanic Garden staff continues to plant all summer long. There is not enough time to get all the planting done only in spring and fall. The garden centers that I have visited recently all still have a great selection of plants grown in containers as well as trees and shrubs that are ready for planting, with their root balls burlapped for protection. The new trees and shrubs are typically dug in late winter or early spring, while they are dormant and held above ground in the garden centers. Production nurseries are limited in which plants can be dug during the summer season. Bare root plant material (with no soil around the roots) is generally planted in very early spring before growth has begun. Bare root plants can be held by suppliers in coolers to extend the planting window in spring, but summer is not a good time for installing bare root plants.

Proper watering of plants before and after planting is much more critical during the hot summer season. Plants can be quickly damaged during hot and dry spells if they are not watered enough and can quickly dry out while sitting above ground before installation. It is important to keep plants moist before planting to minimize stress on the new plant material. The growing medium of containerized plants can sometimes be difficult to moisten if they are planted in your beds when dry. It is best to water them before planting if the pots have dried out. Plants that are grown in containers have a lighter growing medium that generally dries more quickly than garden soil and thus need more frequent, light watering until the roots grow out into the surrounding soil. This may mean watering a couple times a week during very hot periods for the first few weeks.

Newly installed balled and burlapped plants need about 1 inch of water a week — be sure the root ball is getting watered. Watering by hand with a garden hose at the base of the tree or shrub works best and will likely need to be done occasionally, even if you have a sprinkler system. Evergreen trees can shed water away from the root ball when a sprinkler is used. The garden bed will then be moist while the root ball of the tree is dry. In time, the roots will grow out into the bed, but you need to focus on moistening the root ball throughout the summer. The amount and frequency of watering will vary depending on the soil conditions in your garden and weather conditions. Sandy, very well-drained soils dry out more quickly than heavier clay loam soils.

Go ahead and plant this summer. There is no need to wait until next spring. Then mulch the new plants to improve the appearance, prevent weeds and help conserve soil moisture.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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Spring-flowering bulbs do not require much maintenance

Posted in Chicago Botanic Garden, Going green, Topics Of Interest on May 17, 2025| Leave a Comment »

Cutting daffodil foliage back too soon can reduce the vigor of the bulbs and flowering the next year. | RJ Carlson/Chicago Botanic Garden

By Tim Johnson | Published in the Chicago Tribune

I planted some bulbs last fall and am admiring the flowering results. Can you offer some tips on how to best care for them now?

— Emily Spiewak, Niles

The bulbs flowering in my garden at home are putting on a great show as are the ones at the Garden. Spring-flowering bulbs are very effective for bringing early color into the garden. Bulbs do not require much maintenance. They prefer to be planted in an area that is moist in spring and fall and dry in summer. Most bulbs will not perform well in beds that are consistently moist or watered heavily throughout the summer. An important part of being successful with bulbs, like with other plants, is choosing the correct ones for the growing conditions in your garden. Take photos of your garden beds now to guide you in selecting and ordering bulbs for planting this fall. The photos will show you where to plant new bulbs in the fall and help you decide which to choose. Plant daffodils, hyacinths and ornamental onions if you have rabbits or deer browsing in your garden. Tulips and crocuses tend to be eaten quickly as they emerge from the ground in spring. Spray your bulbs with a repellent if you are having issues with animals. Rotate different repellants and reapply after rain.

There is a strong temptation to cut back bulb foliage too soon as the weather warms and the foliage looks increasingly worse. It is better to wait until bulb foliage has gone dormant before cutting it back. The leaves will turn yellow to brown, and once the leaves have all turned yellow, it is OK to cut them back. The bulbs need their leaves to photosynthesize and make food that is then stored to produce foliage and flowers next year. Cutting foliage back too soon can reduce the vigor of the bulbs and their flowering the next year. Tying up the leaves, bending them over and braiding the leaves are not good practices, as they reduce the leaf surface for photosynthesis. If you have planted bulbs in a lawn, hold off on mowing the lawn in these areas to give the bulbs time to go dormant. You will probably need to cut the grass before the bulbs are completely dormant, so set the mower at the highest setting to save as much of the foliage as possible.

I do not fertilize my bulbs, but I leave the leaves on my garden beds for natural nutrient recycling. Your bulbs will get adequate fertilizer if you fertilize your garden beds. Phosphorus is often recommended for bulbs, but this nutrient does not readily move through the soil, so surface applications of it do little good for the plants in your garden. Many garden soils already have adequate levels of phosphorus for plants to perform well in this region. Test your soil if you want to know for sure. If an established patch of bulbs starts to bloom less and less or begins blooming sparsely, the bulbs may have become overcrowded or the planting site may be too shady. That’s the signal to dig and divide or move bulbs to another location. The first step is to lift the bulbs from the ground, being careful to dig the bulbs and not pull them up by the foliage. Take care when digging that you don’t damage the bulbs themselves. Start digging a few inches away from the plants and wait until the bulbs are loosened. The best time to move or divide bulbs is when the foliage has gone dormant (meaning the leaves have finished producing food for next year’s flowers) and you can still see their location.

To divide bulbs, carefully pull the small bulbs from the base of the plant to increase plant numbers and gently separate them so that they can be planted with more spacing in their new location. The larger the small offset bulbs are, the sooner they will flower. Check the original bulb for firmness. If it appears to be in good health, go ahead and replant it; you may still get several years of flowering. If it appears shriveled or damaged, toss it.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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Forest Preserves of Cook County February 2025 Newsletter

Posted in Chicago Botanic Garden, Crabtree Nature Center, FPDCC, Horizon Farm on February 27, 2025| Leave a Comment »

Visitors to grasslands might sight a short-eared owl during the daytime — unlike other native owl species in the Forest Preserves—while they hunt prey such as mice and voles. | Short-eared owl (Asio flammeus), Photo by: Phillip Stosberg

In this issue:

  • We Are Here for You
  • Forest Preserves Achieves American Humane Certified™ Distinction for Animal Care, Welfare and Wellbeing
  • Survival in the Forest Preserves: How Wildlife Takes on the Winter Elements
  • Segregation in the Forest Preserves: A History Lesson
  • Representation on the Slopes: Sagawau Celebrates Black Skiers
  • Latest News: Help Make the Trails Safer for Everyone with Cook County’s Safety Action Plan; Applications Open for Youth Outdoor Ambassador Program; Chicago Botanic Garden’s Annual Orchid Show Open Through March 23; The Forest Preserve Foundation Helps Sustain the Forest Preserves We Love
  • Upcoming Events
  • Volunteer Opportunities: Group Litter Cleanups

Read more here.

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Go large when pruning tree limbs

Posted in Chicago Botanic Garden, Chicago Tribune on February 2, 2025| Leave a Comment »

Be careful not to damage the bark or the trunk as you are pruning. | RJ Carlson/Chicago Botanic Garden

By Tim Johnson | Posted to the Chicago Tribune

There are some large limbs hanging too low over my patio that I need to address before spring. Can I just prune these branches to create more clearance over my patio?

— Jim Young, Libertyville

Winter is a great time to prune the trees in your garden. You should not have any problems pruning off the low limbs to provide more clearance for the patio. In most situations, it is better to remove a larger branch rather than cutting off the ends of branches and leaving unsightly stubs as I see in many home gardens. Be careful not to damage the bark or the trunk as you are pruning. When you cut off a tree branch, the tree forms a callous tissue that covers the wound and seals it to keep out disease and decay.

Use a series of three cuts to remove the limbs. Make the first cut on the underside of the limb approximately 6 to 12 inches away from the trunk and about a quarter of the way through. Then make another cut just outside of this notch on top of the branch that goes completely through the branch. The cut that you made under the limb will keep the bark from splitting or tearing down the main trunk as the branch falls. In some situations, I prune off sections of a large limb to reduce the weight of the limb before making these cuts. The distance that the undercut is from the trunk may vary depending on the size of the branch you are removing. A 1-foot section of a large limb can also damage the trunk as it falls. In these cases, I support the stub with my hand so it does not fall before the final cut is all the way through. Pay attention to your position when pruning these limbs so that you are not knocked off a ladder or in the way of a potential falling limb. Heavy branches can roll unexpectedly as they fall and as they hit the ground. Consider hiring an arborist to prune branches that are 6 inches or larger in diameter if you do not have any experience with pruning large limbs.

The last cut should be made just outside the branch collar that you can see as a swollen area where the branch connects to the trunk. Sometimes this area appears with wrinkled bark. This will allow for proper healing and closure of the wound. The branch collar looks different on different types of trees and can be hard to see on some trees. Certain evergreens, for example, have a branch collar that is flush with the trunk or slightly recessed. It is also important to avoid leaving a stub of branch by cutting too far outside of the branch collar. Generally, there is no need to apply paints, wound dressings or chemical formulations of any type to the surface of the cut. The best practice is to make a clean cut just outside the branch collar using sharp tools.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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Tips for thriving winter houseplants

Posted in Chicago Botanic Garden on January 12, 2025| Leave a Comment »

With the proper precautions, you should be able to continue purchasing plants, including moth orchids, all winter long. (RJ Carlson/Chicago Botanic Garden)

By TIM JOHNSON | Chicago Botanic Garden

Even though it’s winter, I’d like to buy some houseplants and would appreciate some advice on what to consider.

— Emily Jacobsen, Barrington

The winter gardening season is a great time to focus on houseplants and build a
collection. I filled my parents’ living room with houseplants while growing up and I’m thankful for their patience during that time. The most important consideration when buying houseplants or short-term flowering plants in the winter is to protect them from cold temperatures while transporting them. With the proper precautions, you should be able to continue purchasing plants all winter long. Try to avoid buying them on extremely cold days that are below 20 degrees Fahrenheit, because it is harder to protect them. The days in winter that reach into the 30s feel warm to us, but can quickly damage more sensitive plants when they are exposed to the cold. Most garden centers wrap plants to protect them from cold temperatures. If they don’t, be sure to ask them to wrap the plants for you. Wrapping the plants also protects them from breaking in transit.

Place the plants in a stable location in the car for the trip home so that they do not tip over as you accelerate, brake and make turns. Hold them carefully if you are on a train or bus too. When transporting plants, the vehicle should be warm before putting the plants in it, especially if outdoor temperatures are below freezing. The colder the temperatures, the more important it is to warm up the car. Plants should never be transported in a cold trunk or allowed to sit in a cold car for any length of time. Make the garden center your last stop for errands if you are going to buy plants.

It is best to set the plant on a stable surface at home and carefully tear or cut the
wrapper from the bottom up to unwrap the plant. Do not attempt to pull the wrapper off the plant as you risk breaking stems, flowers and leaves. Don’t allow plants to remain in their wrappings for more than 24 hours. Open the top to allow the plants to get air if you cannot remove the entire wrapping right away.

Look for plants that can tolerate low light levels as most home environments have limited sunlight in the winter for growing houseplants. Check new plants to make sure their containers have a drainage hole in the bottom. It’s a good idea to carefully check for any insect pests before bringing a plant home and keep it separate from your other plants for a short period of time to make sure it is pest-free. New plants may lose some leaves as they adjust to a new growing environment, so don’t worry if you notice a few leaves on the table or ground.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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Don’t let up on plant protection this winter

Posted in Chicago Botanic Garden, Topics Of Interest on January 5, 2025| Leave a Comment »

Wrap plant trunks with fine mesh hardware cloth or wire fencing with holes ¼ inch or less in diameter. | RJ Carlson / Chicago Botanic Garden

By TIM JOHNSON | Chicago Botanic Garden

I am new to gardening in this area and wondering if there are any maintenance practices I should use to prevent animal damage in my garden. I have heard that deer can be a big problem.

— José Alvarez, Highwood

Many gardeners drop their guard in winter, giving animals an opportunity to do significant damage to garden plants. I have run into problems in past years from not routinely checking my plants through the winter. Rabbits, voles and mice often chew on the bark of shrubs and young trees during the winter months. This damages the inner cambium layer and affects the flow of water and nutrients between the roots and foliage. When the bark is damaged all around a trunk or stem, the plant may die above that point. Trees and shrubs that are well established and healthy should resprout from live tissue below the damage but still may not be worth saving in some cases depending on the type of plant. If the bark has been completely eaten at ground level, many plants will die. Single-stem trees are typically ruined when they are completely girdled unless you can retrain the tree into a clump form. Deer can do serious damage to yews and arborvitae from browsing foliage up to about 6 feet. It’s easy to miss the damage until it becomes significant if you are not paying attention. Snow cover does not prevent damage these animals can do.

Damage can be prevented by clearing herbaceous plants away from the base of plants to reduce cover and make it harder for pests to hide from predators such as hawks and owls. Wrap the plant trunks or surround shrubs with fine mesh hardware cloth or wire fencing with holes ¼ inch or less in diameter. The material should be pinned to the ground or buried 1 to 2 inches beneath the surface of the soil and may need to be as high as 4 feet to prevent rabbits from causing damage during winters with deep snow cover. Wrapping individual stems with tree wrap can also work to deter rabbits, voles and mice from feeding on the bark. Larger-diameter plastic corrugated cylinders can also be used by splitting them lengthwise and placing them around tree trunks. Repellents may also be used, but they wash off over time and must be reapplied and are generally not as effective. Repellents can be reapplied when temperatures are above 40 degrees Fahrenheit. A dog can help dissuade rabbits and deer from browsing in a yard. (My three dachshunds must be defective! They simply look at the resident rabbit in my backyard and do not give chase.)

It is important to continue monitoring your garden for animal damage throughout the winter. Install or adjust barriers as needed. Look for gnawed bark at the base of trees and shrubs as you walk through your garden. Rabbits can cause considerable damage over the course of winter by feeding on shrubs. As snow piles up, they reach higher and higher to eat. Chicken wire works well to exclude rabbits. Deer will also browse plants during the winter. Gardeners try hanging soap or hair in branches as well as other techniques, but most do not actually repel deer browsing. Use physical barriers such as wire or netting or chemical repellants to protect plants from deer. Yews and arborvitae are deer favorites and will very likely be browsed in areas where deer are active. I have three small yews close to the front of my house in an area where there are deer and have not had any browsing issues yet. Deer occasionally show up in my backyard during spring, summer and fall. In your Highwood neighborhood, deer browsing very well may be a problem.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.

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