Champaign County Master Gardener and Horticulture Program

08/31/2026

Hydrangeas that bloom on old wood – Bigleaf, Oakleaf, and Climbing Hydrangeas – are best pruned immediately after flowering to avoid cutting off next season’s blooms. These hydrangeas can be pruned until about the end of August.

Bigleaf hydrangeas (H. macrophylla) have attractive, long serrated leaves and large, round flowers. Bigleaf varieties include ‘Nikko Blue’ and ‘All Summer Beauty’ as well as repeat bloomers like ‘Endless Summer’ which blooms on new and old wood.

Oakleaf hydrangeas (H. quercifolia) leaves look like those on an oak tree and produce massive, upright, cone-shaped flowers.

Climbing hydrangea (H. anomala subsp. petiolaris) is a climbing vine and a vigorous grower, with flat clusters of white flowers.

details proper pruning techniques at: https://extension.illinois.edu/blogs/good-growing/2022-03-10-how-properly-prune-hydrangeas. University of Maryland Extension offers a Guide to Pruning at: https://extension.umd.edu/resource/pruning-hydrangeas/ including a simple “do no harm” approach to pruning all varieties of hydrangeas. The guide suggests:

– Removing winter-killed wood in the spring;
– Rejuvenating by removing the oldest wood in spring to encourage new growth; and
– Deadheading (removing spent flowers) is the safest pruning technique and can be done anytime.

Smooth hydrangea (Hydrangea arborescens) and P*e Gee hydrangea (Hydrangea paniculata) bloom on new wood and should be pruned in late winter or early spring.

08/28/2026

Love planting bulbs but hate seeing your hard work become dinner for hungry critters? 🌷🐿️ Join Brent Heath of Brent and Becky’s Bulbs for a Zoom Lunch and Learn on Pest Resistant Bulbs. Discover naturally pest-resistant varieties, remedies to make bulbs less appetizing, and physical barriers that can help protect your garden from deer, rabbits, squirrels, voles, and more.
Register today at go.illinois.edu/CCMGbulbs

08/26/2026

If you have been checking your milkw**d for monarch caterpillars the past few weeks, you may have noticed some other critters feasting on the milkw**d. Several insects feed on the milkw**d plant besides monarch caterpillars. The most common ones are milkw**d bugs, milkw**d beetles, the milkw**d tussock moth caterpillars, and aphids.

The toxins in milkw**d give monarchs a bitter taste, protecting them from predators. Other insects also take advantage of this natural protection. The milkw**d tussock caterpillar, or milkw**d tiger moth, is a hairy black, white, and orange caterpillar, often seen in small groups from mid to late summer. Like the monarch caterpillars, it feeds on the leaves, often leaving them skeletonized. They generally feed on the older shoots, while monarchs prefer younger shoots, so the two species are not in competition with each other.

Milkw**d beetles are orange-red with black spots. Two of the most common types are the red milkw**d beetle and the swamp milkw**d beetle. Each has its preferred food, the red beetle preferring common milkw**d, while the swamp beetle, as its name suggests, is more often found on swamp milkw**d. They feed on the leaves, buds and flowers of the milkw**d plant.

Then there is the milkw**d bug, a true bug, which means they have specialized, piercing mouth parts. These are red and black and feed on the sap and seeds of milkw**d plants. They are often seen on other species of Asclepias, like butterfly w**d. Because they are often seen in large groups, the sight of them may cause alarm for some gardeners, but they do little damage to the plants and shouldn’t be a cause of concern.

Another insect often found on milkw**d plants is an aphid, specifically the oleander aphid which is bright yellow with black legs. Unlike the other insects feeding on milkw**d, this aphid was introduced from the Mediterranean region but is now found through much of North America. It sucks sap from the plant tissue, and if there are large colonies of them, they can stress or even kill small or new plants. They can be dislodged with a strong spray of water or by using insecticidal soap or neem oil. But keep in mind, this could also affect monarch caterpillars, so it is generally not recommended. They do have some natural predators which may also help to control the population.

The bottom line here is that all of these insects are harmless and best left alone. If you are concerned about them, plant more milkw**d so that there is enough for all of these creatures to share!

For more information and photos of these common insects, check out the University of Wisconsin Extension https://hort.extension.wisc.edu/articles/common-milkw**d-insects/ or this article from the Illinois Extension https://extension.illinois.edu/blogs/good-growing/2021-07-30-more-monarchs-what-are-those-bugs-my-milkw**d

08/24/2026

As gardeners are babying their flowers and vegetables through the heat of summer, the w**ds are having a heyday. They love hot dry weather but can adapt to just about anything. Weeds have a lot going for them: they thrive almost anywhere, they grow quickly, they mature and produce flowers in a short period of time, and then produce an abundance of seeds that are easily dispersed. Weeds are also hardy enough that they bully for space, shading out other plants or taking over an area and stealing water and nutrients from the desired plants.

A particularly tenacious summer w**d invading gardens now is hedge bindw**d (Calystegia sepium). Hedge bindw**d is a perennial with dark arrow shaped leaves with a pointed tip, about 2-4 inches long. It has white/pink flowers similar to a morning glory. It reproduces by seeds and rhizomes. When removing bindw**d, remove all parts because it can develop new roots on a piece as small as 1 inch long. Hedge bindw**d usually climbs and can easily be mistaken for morning glories. It is a stealthy strangler. Once it has taken hold, the lower stems, almost wiry with no leaves, are hard to see to remove. You must count on the leaves to guide you. This w**d winds itself around twigs and stems, can meander through an entire shrub if you don’t catch it early. See University of Maryland Extension at https://extension.umd.edu/resource/hedge-bindw**d

Field bindw**d (Convolvulus arvenis) is very similar to hedge bindw**d, and as the name suggests, is usually found in open spaces. It starts blooming in late spring and may continue up to early fall. In early spring it is very noticeable in farmlands with many small pale flowers dotting the fields. The flowers are trumpet shaped, pink or white, 1-2 inches wide, and usually open in the morning and close in late afternoon. The leaves are alternate, arrow-shaped, like hedge bindw**d, but with a rounded tip, and smaller. Although the flowers only last a day, they produce seed capsules that may contain 8 seeds. The vines usually sprawl rather than climb and can spread out to 4 feet. They have a tap root that can go as far as 20 feet deep! Seeds can stay viable in the soil for several years. This w**d spreads by both underground roots and seeds. If you pull, be sure to get as much of the root system as possible. A piece only an inch long can regenerate into a new plant. See Cornell University at: https://cals.cornell.edu/w**d-science/w**d-identification/bindw**d-identification/field-bindw**d

For best control, be sure to correctly identify and get after w**ds when they are young when they are easier to pull and have not yet produced seeds. Bindw**d can be managed by cutting, pulling, mowing, and using herbicides. To help avoid recurrence, mulch flower beds, keep lawns mowed high as it is harder for bindw**d to grow in dense turf. For more information see which has a good document with information on bindw**d removal: https://hyg.ipm.illinois.edu/article.php?id=991

08/22/2026

🌷 If critters treat your bulb garden like an all-you-can-eat buffet, this Lunch and Learn is for you. Join us on Zoom as third-generation bulb grower Brent Heath shares his expertise on Pest Resistant Bulbs and learn which bulbs critters avoid, how to protect vulnerable favorites, and ways to keep those bulb monsters at bay!

Register at go.illinois.edu/CCMGbulbs

08/21/2026

Good information about trees.

Trees are heavy lifters in the landscape - they provide shade, filter water, give wildlife food and a place to life and they increase home values. So they're worth investing in and taking care of! 🌳

Give trees a limb up
• Plant the right tree in the right place. Pick a tree that will thrive at a specific site, depending on sunlight, soil pH, root space, and how close it is to other structures. Trees take a long time to grow, so a planting problem may not be apparent for years.

• Maybe the problem isn't the pest. Pests and pathogens are often the symptoms of bigger problems. Trees with yellowing leaves, thinning branches, or splitting bark may be stressed and in a decline spiral.

• How can you diagnose a tree? Look at it from root to shoot.
- What's normal for that species? How old is it?
- Roots: Is a root flare visible above ground? Has there been construction nearby?
- Trunk and branches: Is there damage from mowers or animals? Are there cavities or splits?
- Foliage: Is it wilted or discolored? Dropping leaves early? Are there spots, holes, or bumps?

Explore more with the Everyday Environment team for a conversation about tree care with horticulture Educator Sarah Vogel at https://extension.illinois.edu/blogs/everyday-environment.

08/19/2026

Have you noticed wispy webs like flat horizontal sheets in your lawn or on your shrubs this summer? Sometimes webs can be found in stairwells or around your potted plants. They are very obvious in the morning as they glisten with the dew. These are the work of funnel weaver spiders, or more commonly, funnel spiders or grass spiders, Agelenopsis pennsylvanica. These are medium sized spiders (1/3 to ½ inch) that are often brown with dark stripes on their backs. The females are larger than the males. This species is common across the United States. Taking a close look at the webbing, you may see a tunnel, or funnel, which often is constructed next to a shrub or higher grass to better hide and protect the spider, but chances are you won’t see the spider! They are very fast and wait inside their tunnel until prey approaches. Then they shoot out of their tunnel and subdue their prey.

Grass spiders are usually most active in late summer to early fall. Females are around 1/3 to ½ inch with males being slightly smaller. They feed on a variety of insects, and it has been found that humans bitten by these spiders can have symptoms from swelling or rashes, even back pain, for up to 14 days, so look, don’t touch! Mating takes place from late August to September with eggs produced in October and November. The female stays with the eggs until she dies. The number of eggs in an egg sac ranges from 18 to 236 eggs, often laid under tree bark.https://www.inaturalist.org/taxa/143215-Agelenopsis-pennsylvanica According to iNaturalist: “This small species has been used to study pre-copulatory cannibalism, boldness, aggressive foraging behavior, and the influence of microbes in the reproductive cycle and mating behavior.” https://www.inaturalist.org/taxa/143215-Agelenopsis-pennsylvanica

For more information on these interesting creatures, plus pictures, see:

https://bugoftheweek.com/blog/2015/9/28/spiders-in-the-mist-funnel-weaving-spider-pennsylvania-grass-spider-iagelenopsis-pennsylvanicai, https://ohioline.osu.edu/factsheet/ent-76,
http://schoolipm.illinois.edu/funnelwebspiders/

One interesting note, in Australia, several funnel spiders are considered dangerous, in fact the Sydney funnel web spider has been listed as one of the most dangerous spiders in the world. They inject a potent venom that can affect the human nervous system. https://australian.museum/learn/animals/spiders/spider-facts/ So be glad we have our safer North American varieties!

08/17/2026

Bearded iris are a beautiful addition to any garden, coming up and blooming in the spring when many plants are still sleeping or just coming up. As iris rhizomes (the root) mature, the “mother” produces more rhizomes, so the clumps can become quite large in a few years. When bloom production slows down on your iris (approximately every three to five years), it is time to divide the clumps by removing the old big rhizomes and replanting the small rhizomes. It is important to divide the clumps after flowering when irises become dormant. The best time to do this is during late summer, which reduces the chance of bacterial soft rot on the rhizomes but allows enough time for them to re-establish roots prior to winter. It is important that the roots of newly planted irises become established at least four to six weeks before the first hard freeze or killing frost.

To divide, gently dig up the entire iris clump with a spade or garden fork. You can then divide the rhizomes by pulling them apart with your hands and then clearing off the excess soil. The rhizomes will typically break off at a joint. Use a sharp knife if needed to separate them into smaller sections or to keep newer shoots that should be separated from old sections. Each rhizome you keep should be about as thick as your thumb, have healthy roots, and one or two leaf fronds. Older rhizomes that have no leaves should be discarded. It is important to inspect each rhizome for insects such as iris borer or smelly rotting areas as these should be destroyed and not placed in your compost area. Finally, cut the leaf blades to about one third of their height so that the rhizome focuses on putting energy into the root not the shoot.

When you are ready to plant, and for the best display, place them individually or in groups of three so the fan of the leaves face the same direction. Lay out your design by spacing the plants 12 to 18 inches apart (may be closer for dwarf varieties, or farther apart for taller varieties). Dig a shallow hole bigger than the rhizome (approximately 4” deep). You will then add back some loose soil to make a good bed to center the rhizome on and spread out the roots and backfill with soil. The top surface of the rhizome should be slightly visible at the soil surface. It's a very common mistake when replanting irises to place them too deep. Be sure to press down on the soil firmly to anchor the rhizomes in place. Newly planted rhizomes should be watered thoroughly. Do not mulch garden areas that are planted with iris, as mulching retains moisture and could cause your rhizomes to rot.

To learn more and to see photos and even a video of the process, please visit https://extension.illinois.edu/blogs/good-growing/2021-08-20-how-divide-and-plant-bearded-iris or https://extension.umd.edu/resource/dividing-iris/.

08/12/2026

Do you have tons of tomatoes? Piles of peppers? Zillions of zucchinis? Oodles of onions? If you have excess fresh produce or herbs, there are nonprofit organizations that would be thrilled to accept your donations and distribute to those in need. There are several places in Champaign-Urbana that accept fresh produce. If you have something to donate, find a pantry near you, call first, preferably before you harvest, to verify when they can accept your produce, and let them know what you have to offer.

The Eastern Illinois Foodbank: The Foodbank at 2405 N. Shore Drive, Urbana, welcomes donations of fresh produce from your garden or farm. Please plan to drop your donation off during warehouse hours, (7am - 4:00pm Monday through Thursday and Friday 7am - 12:00pm). https://www.eifoodbank.org/action/donatefood/

The Daily Bread Soup Kitchen: Food Donations can be dropped off at the alley door of DBSK, at 116 N. First Street, Champaign, between the hours of 8:30 a.m. – 12:00 p.m., seven days per week. https://dailybreadsoupkitchen.com/donate/food-donations/

Give Back Garden (CUPHD Lobby): Drop off extra backyard or garden harvest at 201 W. Kenyon Rd., Champaign (WIC desk on the left side). Hours are Monday–Friday, 8:30 a.m. – 3:30 p.m. Produce should be lightly cleaned, dry, and ideally bagged and labeled. https://www.c-uphd.org/community-food-initiatives.html

If you are not located in Champaign-Urbana, AmpleHarvest.org is an online service that helps connect gardeners who want to donate excess garden produce to nonprofit organizations that accept and distribute the produce to those in need. At https://ampleharvest.org/find-pantry/, you will find a search engine to help you identify food pantries and soup kitchens by zip code or by location name.

This Illinois extension website also has a list of the commonly donated garden vegetables and how to clean and prepare them for donation. https://extension.illinois.edu/blogs/good-growing/2023-07-21-abundant-harvest-donating-garden-crops-food-pantries

Don’t let excess produce rot in the garden or get tossed in the trash. Put it to good use by donating it!

08/10/2026

One of the prettiest annuals blooming right now (to first frost) in central Illinois is lisianthus, Eustoma grandiflorum. Other names for it are Prairie Gentian or Prairie Rose. The flowers resemble petite roses and come in similar colors of white and pink, with purple for variety. Its foliage is also striking a blue-gray-green color, with delicately slender stems. Varieties are available at heights ranging from 6 to 30 inches.

Used as a cut flower in the floral industry, lisianthus is popular in bridal bouquets. Home gardeners can enjoy the cut stems inside for several days. Lisianthus is not known as growing well from seed. Success in growing is aided when buying small plants from local nurseries or online. This author has not found any local nurseries that offer transplants in the spring, but was able to buy them online and is successfully growing them in a flower bed. Because they are quite slender plants, they either should be supported or staked in some way or planted six to eight inches apart so they support each other.

Lisianthus need full sun (six to eight hours of sun a day), well-drained soil, and should be kept moist.

More information about this beautiful, maybe unfamiliar, plant is available at: Iowa State University Extension: https://www.extension.iastate.edu/newsrel/2002/sep02/sep0230.html; North Carolina State University Extension: https://plants.ces.ncsu.edu/plants/eustoma-grandiflorum/ and University of Florida Extension: https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/lisianthus/.