2017 Master Gardener Classes

The following Agriculture & Natural Resources article printed in the Summer 2017 edition of the quarterly Oldham County Extension newsletter.

Master Gardener Classes Begin in September

Master Gardener classes will be offered Fridays, beginning September 1 through November 17. Classes will meet from 9:00 a.m. to 11:00 a.m. at the extension office. The cost for this program is $100 to cover class materials. Registration forms are available in our office as well as online at oldham.ca.uky.edu/OC-Master-Gardeners.

oldham county master gardeners

What is a Master Gardener? A Master Gardener is someone who has successfully completed Master Gardener classes offered by an extension office. Classes provide research-based information on core subjects ranging from botany to soils to plant pests. Trees, turf, and landscape plant growing principles are also covered. Master Gardener volunteers take the knowledge learned through these classes and put it to use in their communities – sharing knowledge informally with others, teaching, and doing various gardening-related work in public areas.

How do I become a Master Gardener? Complete classes offered at the extension office and complete 40 hours of volunteer service within one year of course completion. Volunteers complete 20 service hours annually in subsequent years to maintain active Master Gardener status.

oldham county master gardeners

Where can I volunteer? There are several ongoing volunteer opportunities at Yew Dell Gardens and Creasey Mahan Nature Preserve, plus one-time opportunities that are announced throughout the year. Participants may help with an existing project or begin their own. A project can be as simple as helping plant or maintain your church’s landscape or providing plant recommendations for a neighborhood association common area. The possibilities are endless.

Ag Clubs Update: Cattlemen, Green Thumbs, Master Gardeners

The following Agriculture & Natural Resources articles printed in the Summer 2017 edition of the quarterly Oldham County Extension newsletter.

Oldham County Cattlemen’s Association News

The Oldham County Cattlemen’s Association will meet on July 18 at 6:00 p.m. at the extension office. The meeting will feature guest speaker Jim Akers of Blue Grass Stockyards. The association welcomes new members – pick up an application at our office or join online at www.kycattle.org. Annual $35 membership dues cover membership to both Oldham County and Kentucky Cattlemen’s Associations, a subscription to Cow Country News, and meals at county meetings.

oc cattlemen's association

Charlie McDonner of Whayne Supply was a guest speaker and sponsor of the Oldham County Cattlemen’s Association March meeting. Members elected officers for the current year: Maynard Stetten as president, Paul Bradshaw as vice president, and Jerry Bennett as secretary/treasurer.

Plant Sale & Auction Benefits 4-H

For the second year in a row, the Green Thumbs Garden Club held a spring plant sale and auction to benefit Oldham County 4-H. Green Thumbs and Oldham County Master Gardeners collected plants, containers, garden sculptures, and other garden decor for the event. This year, the clubs raised a total of $1,284, roughly a hundred dollars more than last year! This generous donation will be used as scholarships to send Oldham County children to 4-H camp in the summer.

Thank you Green Thumbs and Master Gardeners for your continued support!

KY Spring Native Flowers

Home to over twenty-five hundred plant species, Kentucky is a veritable wildflower garden. Kentucky native spring flowers include bloodroot, spring beauty, and Virginia bluebells.

KY native wildflower

Bloodroot

Spring Kentucky Native Flower

One of the earliest blooming wildflowers in Kentucky, bloodroot (Sanguinaria canadensis) appears in the late winter and early spring. This native wildflower gets its name from its red-orange rhizome and the red juice that can be squeezed from it. Native Americans used bloodroot to treat fever, ulcers, ringworm, and skin infections. It finds use in dye-making and is also being studied for possible anti-cancer properties. Bloodroot, however, is toxic when ingested, causing vomiting and loss of consciousness.

Bloodroot can be planted from seed or through root division. It can grow in sun or shade as long as rich, moist soil is available. You will find this short wildflower in both Kentucky’s woodlands and open fields. Bloodroot’s white flowers, yellow stamens at the center, are about an inch and a half to two inches across. A single round leaf accompanies each flower.

KY wildflowers in blooms

Spring Beauty

Kentucky Spring Wildflower

Spring beauty (Claytonia Virginica) is another of Kentucky’s early spring wildflowers. Less than a foot in height, the small white to pink flowers emerge before the trees begin to leaf out. Spring beauty opens in the morning to take in the sun’s warmth and closes again each evening. Its inconspicuous leaves blend in with surrounding grasses. Like many wildflowers, its loveliness is fading, blooms lasting only a couple weeks.

Claytonia readily reseeds itself and can be found soaking up the sun across the eastern United States. Gardeners can collect the seeds to bring a little spring beauty to their own gardens.

Spring beauty owes its name to John Clayton, an eighteenth century naturalist who so impressed Benjamin Franklin that the founding father “granted him free mail privileges for shipping his plants and letters.”

KY wildflowers in bloom

Virginia Bluebells

Ephemeral KY Native Wildflower

When traversing Kentucky’s woodlands in the early spring, you may encounter Virginia bluebells (Mertensia virginica), also called cowslip or mertensia. Virginia bluebells flourish in sandy and loamy soil and can often be found along creeks and other waterways. Nurseries and seed catalogs also carry these spring beauties. The nodding, bell-shaped wildflowers vary from blue to purple to pink. The inch-long trumpets bloom in clusters. Bluebells grow to a height of one to two feet, and if the growing conditions are right, they may quickly spread and naturalize. Bees, butterflies, and moths all pollinate them.

This Kentucky native wildflower springs up after the last hard frost in March or April. A spring ephemeral, Virginia bluebells only bloom for two to three weeks before going to seed. The foliage dies back by early summer. Mass plantings are breath-taking while Virginia bluebells are in bloom, but they are short-lived and may leave a “hole” in your landscape once they have died back. Keep this transience in mind when planting bluebells in your garden.

Virginia bluebells were a favorite of Thomas Jefferson’s and still grow at the Monticello today.

KY Rain Garden Wildflowers

Kentucky Wildflowers

Native Plants Attract Butterflies and Bees

Interested in planting wildflowers for pollinators? Bloodroot, spring beauty, and Virginia bluebells all attract butterflies and bees.

For more information on using native plants to attract butterflies, check out the following resources:

oldham county kentucky gardening

Oldham County Gardening

Upcoming Gardening Classes

Oldham County Extension offers educational classes, the following of which are free and open to the public. RSVP for an upcoming gardening class in Oldham County, Kentucky via (502) 222-9453 or lauren.state@uky.edu. To get notifications of upcoming gardening classes, contact the Oldham County Extension office.

Hellebores
Friday, March 24, 6:30 p.m.
Biologist Anne Cartwright of the American Hosta Society discusses another of her favorite flowers: hellebores. This gardening class is sponsored by the Oldham County Master Gardener Association.

Wildflower Walks With Tavia
Saturday, March 25
Woodland Garden Walk: 10:15 a.m.
Forest Trails Wildflower Walk: 12:15 p.m.
March is a marvelous time to rediscover our scenic landscape and its many inhabitants. Tavia will share share medicinal uses of plants, how they got their names, any fun strategies of how they reproduce, and “flora-lore” and stories that have been told by Native Americans.

Vegetable Gardening
Tuesday, April 11, 6:30 p.m.
Horticulturist Michael Boice will share tips on establishing and maintaining a successful home vegetable garden.

Gardening for Wildlife
Thursday, May 4, 6:30 p.m.
Master Gardener Mike Guelda discusses using native plants to draw in birds, bees, and butterflies. This gardening class is sponsored by the Oldham County Master Gardener Association.

Year-Round Irises
Thursday, May 11, 10:00 a.m.
Bob Strohman, author of the recently published Iris Red, Iris Dead and member of the Louisville Iris Society, shows how to have irises in bloom all twelve months of the year. This gardening class is sponsored by the Oldham County Master Gardener Association.

Photographs by Jennifer Anderson (USDA-NRCS PLANTS Database), Paul Henjum, Christian Hummert, SB Johnny, Ryan Kaldari, Nicholas A. Tonelli, Sudhir Viswarajan. Used under the Creative Commons License.

Written by Lauren State, Oldham County Master Gardener. Reviewed by Traci Missun, Oldham County Agriculture & Natural Resources Agent.

Adapting Your Garden As You Age

Tips For The Aging Gardener

Love gardening but afraid your body can no longer physically handle the work? A few simple adjustments can help make the work easier, allowing you to continue enjoying your hobby.

Like an athlete, the gardener develops gardening skills through repeated activities like digging, weeding, mulching, etc. We learn how to use tools to get the job done with the least amount of efforts and the best results.

gardening tips

Through my wife, an occupational therapist, I have learned a lot about adapting physical activities to fit a person’s ability. Her background includes work with children and seniors.

I have been gardening and landscaping since the late 1970s. Following my back surgery in 1995, I discovered the importance of proper lifting, carrying, and digging techniques for gardening. Recommended habits can be modified. Don’t wait for back surgery to take a look at your gardening habits. I still garden and do strenuous work, but I listen to my body and take a break, change my position, or stop when needed. Well, sometimes I go past my limit — but not far — and when I do, I pay more attention to my posture. Staying active is important to maintain endurance, flexibility, and energy.

The Aging Gardener

When we age, endurance is often the first thing to go. We can’t work as long. We feel weak, unable to lift and move plants like we used to, and familiar tasks take longer to complete. If you’re having these experiences, it might be necessary to reevaluate the size of the garden or change its maintenance requirements. Reduce the overall maintenance of deep perennial beds, for example, by making them narrowing and backing them with shrubs.

The loss of flexibility is also one of the first signs of aging. An injury or development of arthritis are among several things that can cause reduced flexibility. This limits our ability to maneuver in the garden: getting up and down, twisting or changing position while pulling weeds or picking flowers, and cleaning up dead leaves. Of course, gardening does help us maintain flexibility. Reduced flexibility needs to be considered when we decide what needs to be changed to make it easier to maneuver in the garden.

Additional limiting changes include poor balance and persistent back and joint pain. Once these changes start, gardening becomes more of a challenge, so modifying your garden as you develop it could help in the long run.

Adapting Your Garden As You Age

Let’s look at the garden. What is the size and layout of your garden? Is your garden large with numerous perennial plantings and border gardens, or is it smaller, including just the area surrounding your house with maybe a small vegetable garden? The style, size, and area of your garden will determine the approach needed when making modifications so that you can enjoy gardening again.

Note that annual and perennial plantings need a lot of maintenance because of their constant change and growth rate. Lawns, trees, and shrubs also require maintenance but not as often as flower beds.

We don’t want to limit our garden, build expensive raised beds, and, most of all, reduce the size of our garden once it is established because there are always new plants to try. We should look ahead. Look at what has recently changed in your ability to maintain your garden. What are your immediate limitations? Decide what you will be able to handle and still enjoy gardening. Will you be able to have someone available to help (maybe a family member or young gardening enthusiast) to keep your garden as it is?

gardening as you age

Gardens are a collective of plants that we desired to grow at one point or another. Some, though attractive, are not your favorite. Select those plants that are your favorites and reconsider how to handle the rest. Changes based on a landscape plan can be made all at once or over a period of years. If you decide to do the work yourself, start with your most labor-intensive space. Look for plants that need less attention. Reduce the overall maintenance of deep perennial beds by making them narrower then backing them with shrubs. Another solution might be creating a pollinator garden that requires minimum upkeep and can be mown off once a year.

Reduce reaching distance and amount of leaning forward to pull weeds or spread mulch. If you can only access a bed from one side, ensure it is no wider than two feet. Beds accessible from both sides can be four feet in width.

To make the work easier, use quality tools and keep them clean and sharp. A rusty shovel is more difficult to dig with because the soil will stick to it more. A sharp hoe will cut through weeds easier than a dull one. Consider automatic watering and semi-automatic watering systems for gardening to reduce the amount of hand watering. Soaker hoses and single drip emitters are two options.

Making Your Garden More Accessible

Once you have decided what changes to make to your garden, you can make them yourself with family help or hire a landscaper to install them for you.

The design of large gardens will need to provide easy access to all the plants with wide, level walkways on both sides of four-foot-wide beds. Create shaded areas in the garden using trellises, gazebos, and small trees so you can get out of the sun a while. Benches provide a comfortable place to sit and rest.

Walkways should be wide and level enough to accommodate a wheelchair. Turf, smooth recessed stepping stones, or paving stones make a good surface for wheelchair access. Mulch and loose gravel are often hard to push through and can also become a slipping hazard.

Smaller garden areas can be created using a number of large containers grouped together or as single planters.

Container Gardening

container gardening

Container gardening can reducing your gardening stress, and the many different and attractive containers available add interesting focal points to your garden.

You can also turn just about anything into a container garden. From teapots to milk jugs, wooden dressers to wine barrels, let your creativity run wild!

Raised Bed Gardening

Consider installing raised beds that reduce bending over by allowing you to work in a standing or seated position. Standing, you may be able to maintain a three-foot-deep bed, while two feet is manageable if seated.

raised bed gardening

Raised beds can be a very attractive part of a landscape, defining walkways and providing a more formal appearance. Height often varies from six inches to three feet tall. Raised beds can be constructed in many styles using a wide variety of materials, including treated wood, concrete blocks, stone, and more. Various shapes and curves can be included to help blend the raised garden into your existing landscape, making it both attractive and functional.

Vertical Gardening

Unique garden features like vertical gardening with wall planters and trellises allow you to work while standing up. You can buy a premade trellis or build one yourself. Pots can be stacked or arranged on a riser. Like container gardening, vertical gardening is an opportunity to get creative in the garden.

vertical gardening ideas

Growing vegetables using vertical trellises reduces bending and picking. Many vegetables grow well when trellised. Cucumbers, beans, squash, and melons can all climb the traditional store-bought garden trellis.

Straw Bale Gardening

Another simplified gardening method that lifts your garden, making it more accessible, is straw bale gardening. This gardening method can be incredibly productive. It also cuts out all of the digging and cultivating that can be hard on the body. Straw bale gardening does, however, require several weeks of setup. A good guidebook is Straw Bale Gardens – The Breakthrough Method for Growing Vegetables Anywhere, Earlier and With No Weeding by Joel Karsten.

Reduce Your Garden Stress

Every garden and every gardener is unique. Consider your body type and abilities when adapting your garden as you age. Understand that your garden is limited by your physical abilities and personal interests as well as the location of the garden itself.

  • Reduce the overall size of the garden
  • Trade out high maintenance annuals and perennials for lower maintenance shrubs and trees
  • Reduce the amount of reaching, leaning, and bending with raised bed and vertical gardens
  • Garden small with container gardening
  • Keep your tools in good shape so they’re easier to work with

With these tips in mind, make changes that allow you to continue enjoying your gardening hobby without the stress of a high-maintenance landscape.

Written by Michael Boice, Oldham County Extension Horticulture Assistant. Edited by Lauren State, Oldham County Extension Staff Assistant.

Reference: National AgrAbility Project, ‘Arthritis and Gardening: A Guide for Home Gardeners and Small-Scale Producers.’ Purdue University, 2016.

Vegetable Garden Preparation

The following Horticulture article printed in the Spring 2017 edition of the quarterly Oldham County Extension newsletter.

Looking Forward to the Vegetable Garden

Spring is almost here. Take advantage of the last few days of winter to plan your garden. After exploring the seed catalogs and deciding what you want to grow, map out your garden on paper. This is a good way to determine how much seed to order for the vegetables you want to produce. Whether you are growing a new garden or one you have been using for several years, planning will help improve the quality of your harvest this year and future years.

  • Plan your garden on paper before you begin. A map showing where each vegetable is grown allows you to space your plants for good growth. This plan will help determine your crop rotation for following seasons to reduce the carryover of vegetable disease and insect pests in the soil.
  • A good gardening site has full sun for at least eight hours each day and is relatively level, well-drained, and close to a water source. Watch for possible shading as landscape trees mature.
  • Test your soil every two to three years. Prepare the soil properly and add fertilizer and lime or sulfur according to soil test recommendations.

carrot vegetable garden

  • Plan only as large a garden as you can easily maintain. It is easy to overplant and then fail because it is hard to keep up with the tasks required.
  • Grow vegetables that will produce the maximum amount of food in the space available. The bush varieties are best for small spaces and generally yield a lot of vegetables.
  • Plant during the correct season for the crop. Crops are either cool season or warm season types. Choose varieties recommended for your area. Controlling weeds and watering when needed will keep the plants less stressed and improve your production.
  • Harvest vegetables at their proper stage of maturity. Store them promptly and properly if you do not use them immediately.

A well-planned and properly kept garden should produce 600 to 700 pounds of produce per 1,000 square feet and may include many different crops.

ky strawberries

Finally, the closer the vegetable garden is to your back door, the more you will use it. You can see when your crops are at their peaks and can take maximum advantage of their freshness. In addition, keeping up with the planting, weeding, watering, and pest control will be easier.

The 2017 Vegetable Gardening Guides are now available. Contact the Oldham County Cooperative Extension Service office or download the publication “Home Vegetable Gardening in Kentucky” online.

vegetable gardening

Based on article by Richard Durham, Extension Horticulture Specialist, University of Kentucky Cooperative Extension Service. Edited by Oldham County Horticulture Assistant Michael Boice and Oldham County Staff Assistant Lauren State.

KY Native Plants in Bloom

Home to over twenty-five hundred plant species, Kentucky is a veritable wildflower garden. Kentucky native fall flowers include aster, goldenrod, and ironweed.

KY native aster

Aster

Fall Kentucky Native Flower

Several species of aster grow in Kentucky, including smooth blue aster, aromatic aster, New England aster, and white panicle aster.

Kentucky asters bloom from summer to fall in multiple colors: violet, white, blue, and pink. Depending on species and variety, they can grow from eighteen inches to five feet tall. Height can be controlled by pruning during summer, before buds develop. Be careful to remove no more than one-fourth of the total height at a time so as not to overstress the plants.

Asters are prone to powdery mildew and verticillium wilt, especially when overcrowded. Prevent these diseases by providing the plants with good air movement. Asters grow best in full sun but can tolerate partial shade.

KY native goldenrod

Goldenrod (Solidago)

Kentucky Native Flower in Bloom

Goldenrod, Kentucky’s state flower, blooms in the late summer and early fall. Thirty-one species of goldenrod are native to Kentucky, including two endangered species: White-Haired Goldenrod and Short’s Goldenrod.

It is a common misconception that goldenrod is responsible for fall allergies. In truth, it is the inconspicuous ragweed, blooming at the same time, that causes hay fever. Green and weedy in appearance, ragweed blends right into its surroundings. Its tiny, green flowers release waves of pollen into the air, contributing largely to fall allergies. Goldenrod, on the other hand, is insect-pollinated and therefore not the culprit of your allergic reaction.

Goldenrod blooms in full sun from late summer to early fall. Species vary from two to five feet in height. Some varieties will aggressively take over a garden, so goldenrod is not a common landscape plant. They are susceptible to several diseases, but most are easily avoidable if proper air circulation is provided and good watering practices are used.

KY native ironweed

Ironweed (Vernonia)

Kentucky Native Wildflower

From late summer through early fall, ironweed blooms in fields and along roads all across Kentucky. The most common species in the state is Tall Ironweed, but Missouri Ironweed and New York Ironweed also grow in some regions.

Ironweed can grow between four and six feet tall, but pruning in June can help keep the size manageable. It prefers growing in full sun and well-drained, moist soil. Few pests and diseases affect this Kentucky native wildflower. With an aggressively spreading root system, ironweed is perhaps the most troublesome pasture weed in Kentucky. Livestock avoid it due to its bitter taste.

Kentucky Wildflowers

Native Plants Attract Butterflies and Bees

Interested in planting wildflowers for pollinators? Aster, goldenrod, and ironweed all attract butterflies and bees.

For more information on using native plants to attract butterflies, check out the following resources:

Photographs by Greg Hume and SteampunkGypsy. Used under the Creative Commons License.

Written by Lauren State, Oldham County Master Gardener. Reviewed by Traci Missun, Oldham County Agriculture & Natural Resources Agent.

Top 5 Landscaping Mistakes

The following Agriculture & Natural Resources article printed in the quarterly Oldham County Extension newsletter.

ky landscaping

Common Landscaping Mistakes

Horticulturist Michael Boice Shares His Expertise

Planting and managing a landscape incorrectly can lead to plant loss or excessive maintenance. Often we plan a landscape without thinking about the needs of plants or how they grow. Five of the most common mistakes I have found include locating a plant in a space that is too small for it, planting in poor soil types, overplanting, improper mulching, and failing to consider the environmental requirements of the plant.

Trees are often planted in locations they will rapidly outgrow. Even small trees grow 15 to 25 feet tall and 10 feet wide and can interfere with buildings and walkway. Heavy pruning to control the size will eventually stress the tree, making it susceptible to disease and insect pests.

Some locations have poor soil that will not support the plants we choose. Note that water-retaining soils are the most common type in our area, and too much water can drown a root system. Root health is very important to the growth of a plant. Some sites may require total removal of poor soil and replacement with a good quality topsoil to insure proper drainage.

ky landscaping

Overplanting is a common error. It may be desirable for a new planting to look full, so small plants are planted for the immediate aesthetics without considering how big they will grow in a couple years. Overplanting requires a lot of trimming to maintain plant size because crowded plants will grow taller. Crowding also reduces air movement, increasing the opportunity for disease and insects to attack. Plants often have to be removed to reduce the overcrowded look or even to uncover a blocked window. Reduce the maintenance and improve the health of your landscape by considering how much space a plant will require once it is mature.

Proper mulching is good for the landscape. Mulch improves the appearance, conserves moisture, and reduces the number of weeds. Mulch can also cause problems if applied incorrectly. Mulch should be applied a uniform two to three inches deep around the planting. It should not be excessively deep or piled up on plant stems or trunks. Deep mulch can shed water, limit air reaching the roots, and create homes for rodents and insects that can damage the plants. Mulch piled up around tree trunks creates an area where roots will grow in the mulch and wrap around the tree. Over the years, the roots grow toward the trunk and girdle the tree, killing it. Maple trees are especially prone to girdling roots.

Plants used in landscaping come from many different growing environments. Plants chosen to add color or texture are often placed in locations that are too sunny or too shady for them. The plants become stressed, making them more susceptible to pests. Some plant foliage, such as that of the variegated hosta, will burn in sunny locations. Most flowering plants will not flower in heavy shade. The amount of light and water available, soil type, and growing temperature are important for the health of the planting.

ky landscaping

Learning about the plants in your landscape will improve your chance for success and reduce the maintenance required to keep it looking good.

Written by Michael Boice, Oldham County Horticulture Assistant. Edited by Lauren State, Oldham County Extension Staff Assistant.

Kentucky Garden Pests

The following Horticulture article printed in the quarterly Oldham County Extension newsletter.

Managing Home Garden Pests

This year’s wet spring has created an environment favorable for weeds, and disease to develop. It will be important to use Integrated Pest Management (IPM) to have a productive garden. IPM includes using disease resistant varieties, crop rotation, sanitation, weed control, and careful frequent observation.

Planning ahead for your garden is important. By planning, you can determine what you want to grow and how much space is required. Spacing the plants so they are not crowded allows good air circulation, reducing disease development. Choosing vegetable varieties with resistance to several diseases will reduce disease risk. Rotating crops – planting a crop in a different area of the garden from the previous year – also reduces potential disease development. Sanitation too helps reduce the spread of disease or insect pests. Remove all diseased portions of plants and dying plants to eliminate sources of disease. Plants no longer producing should be removed and composted.

Weed control is also part of sanitation. Weeds compete for space and nutrients and can host insects and diseases. Mulch helps control weeds, prevents disease spores splashing up on foliage, and conserves moisture.

armyworm damage

Armyworms damage plants from the bottom up.

Careful observation – inspecting the plants for pests frequently – helps alert you to early problems. The sooner you find a pest, the easier it is to control. Weather conditions indicate when it might be necessary to apply preventive fungicide applications. Looking at the underside of leaves is a good way to spot insects that can be removed before they damage the crops.

armyworm

Garden pest: armyworm on saliva.

Using all of the IPM techniques help to improve the quality of the garden and produce.

The Kentucky Hydrangea

The following Horticulture article also featured in the May/June edition of the Kentucky Horticulture Newsletter.

Growing Hydrangeas in Kentucky

Primarily known as a source of summer color, hydrangeas’ interesting bark and flower heads can also provide winter texture when left untrimmed until spring. Their overall texture is coarse, so they work best in less formal gardens, possibly bordering the property.

Depending on the species, hydrangeas range from three to fifteen feet in height, four to ten feet in width. They grow in full sun to part shade in rich, well-drained, moist soil. Hydrangeas flower June through August — long after most shrubs have finished flowering — in large white, pink, or blue panicles, or clusters. Four species are commonly used in Kentucky landscape plantings.

KY Hydrangea Species – Big Leaf Hydrangea

KY hydrangea macrophylla

Hydrangea macrophylla or Big Leaf Hydrangea is the most widely used hydrangea species in Kentucky. Its large flowers range from white to pink to blue. While white cultivars remain white, pink or blue cultivar color is determined by soil pH and availability of the micro-nutrient aluminum. A soil pH range between 5.0 to 5.5 will generally produce the blue flowers, and a pH of 6 and above inspires pink flowers.

Certain cultivars of Big Leaf Hydrangea are grown as potted plants in a greenhouse to bloom for late winter and spring holidays like Easter. These House Hydrangeas are selected for flower size, ease of flower forcing, but not hardiness. Most house hydrangeas will not produce flowers dependably when planted in Kentucky landscapes without special winter protection. The color of the potted hydrangea’s flowers is pink unless aluminum sulfate is applied to the potting media or landscape soil which lowers pH and turns the flowers blue.

Most cultivars of this species bloom on the previous season’s wood. If temperatures drop too low, the flowers for the next season will be lost. Kentucky is considered zone 6 with possible low temperatures to -10 degrees, and occasionally these low temperatures kill shoots or flower buds, preventing any flowering that year. Breeding efforts to improve blooming characteristics have found several new selections like “Endless Summer” that will bloom on current season’s growth, providing blooms even if flower buds are killed by late spring frosts.

KY Hydrangea Species – Smooth Hydrangea

KY hydrangea-arborenses

Hydrangea arborenses or Smooth Hydrangea is popular for its large, white blooms from June to September every year on new growth. Removing the flowers as they turn brown will encourage a second flush of flowers in August. It grows in full sun to part shade in moist, well-drained soil. Part shade is best in locations where the weather is generally hot and dry. This hydrangea grows three to five feet tall, making it a possible choice in smaller landscape spaces. There are several good cultivar selections, but the most popular is “Annabelle.”

Smooth Hydrangea is a Kentucky native plant.

KY Hydrangea Species – Panicle Hydrangea

KY hydrangea-paniculata

Hydrangea paniculata or Panicle Hydrangea is one of the larger shrubs growing six to ten feet tall and six to ten feet wide depending on the cultivar. This plant will grow best in full sun. Enjoy the white to purplish-pink flowers from June to September. Blooms can be pruned when they turn brown or during the winter. One popular selection of this species is “Limelight” with large, light green flowers that mature to white.

KY Hydrangea Species – Oak Leaf Hydrangea

KY hydrangea-quercifolia

Native to the southeastern United States, Oak Leaf Hydrangea (Hydrangea quercifolia) is known for its large, oak leaf-shaped foliage, is a popular landscape choice for areas with part shade. The white to purplish-pink flowers are four to twelve inches long with three- to four-inch wide panicles. The flowers are abundant and fragrant. In the fall, the foliage turns to shades of red, orange-brown, and purple, adding additional color to the landscape. The Oak Leaf Hydrangea works best in a partly shaded, border planting.

Growing Hydrangeas in Kentucky

To get the most from a planting of these four popular Kentucky hydrangea species, provide a location that will have full sun to part shade. Afternoon shade reduces summer heat and drought stress. Avoid pruning in the fall. Prune after the shrub has bloomed during the summer, giving the shrub time to grow new flower buds for the next season before winter sets in.

A good resource for additional information is Michael A. Dirr’s Hydrangeas for American Gardens, Timber Press (2004).

Written by Michael Boice, Oldham County Horticulture Assistant. Edited by Lauren State, Oldham County Extension Staff Assistant.

Photography by KENPAI, Frank Vincentz, and Anne Norman. Used under the Creative Commons Attribution license.

Bacterial Wilt of Cucurbit Crops

The following Agriculture article printed in the 2015 Winter edition of the Oldham County Extension newsletter.

Cucurbit Crop Bacterial Wilt

Bacterial wilt of cucurbits is often overlooked or undiagnosed in home gardens, but this disease has the potential to cause economic loss for producers growing vegetables for local markets. This disease is specific to cucurbits – a family that includes cucumbers, squash, melons and pumpkins. Bacterial wilt primarily affects cucumber and cantaloupe. Damage to other cucurbit crops is typically less severe.

Bacterial wilt is carried and transmitted by cucumber beetles as they feed on plants. These beetles feed on a wide range of host plants, and the adults can survive winters in protected areas like plant debris or fencerows. Because of their prevalence and overwintering ability, cucumber beetles are likely to be pests each year here. Once cucumber beetles feed on plants infected with the bacterial wilt organism, they carry it in their guts, potentially infecting plants they feed on in current and following season.

Bacterial wilt produces a sticky sap-like substance inside plants. This clogs the vascular system, causing plants to wilt and ultimately die. The substance is visible when plant stems are cut by pulling the knife away from the cut and looking for threads of sticky slime. Once infection has occurred, it is too late to rescue affected plants. Leaf wilt is often the first symptom noticed, followed by wilting of entire vine. Wilted leaves turn dark green, then brown as they die.
Bacterial wilt symptoms may be mistaken for squash vine borer damage, which also causes wilting and plant death. Splitting open the vines will reveal if squash vine borer is the culprit. Look for a whitish caterpillar with a brown head or frass, a saw-dust like material that is evidence of vine borer feeding.

Prevent Bacterial Wilt

Prevention of bacterial wilt in cucurbit crops depends on controlling the cucumber beetle. The first step in doing this is good sanitation – remove and destroy infected plants to prevent beetles from overwintering in debris. Because cucumber beetles also feed on flowers, sanitation of nearby flower gardens is also imported. Remove dead annual flowers, dead lower leaves of perennial flowers, fallen leaves and other debris that could provide an overwintering site for cucumber beetles.

Excluding cucumber beetles with use of row covers or screens can be an effective control in small plantings. A disadvantage of this control is that covers must be taken off before bloom to allow for pollination.

Preventive insecticide application is another option, but application must begin as soon as seedlings emerge or soon after transplant to prevent beetle feeding and disease transmission. Check UK’s Home Vegetable Gardening and Commercial Vegetable Production Guides for insecticide recommendations: UK Department of Horticulture.

Written by Traci Missun, Oldham County Agriculture & Natural Resources Agent. Edited by Lauren State, Oldham County Extension Staff Assistant.