Master Gardeners

Extension has a vast collection of resources addressing horticultural interests across Illinois. We recognize that home and commercial horticulturalists have unique needs, so we've cultivated resources designed to address their top concerns. These collections represent the topic areas where we usually get the most questions, but our expertise covers everything from trees to tomatoes to tulips.

green plant leaf with brown spots

Plant Clinic

Plant disease and injury can be costly. The Plant Clinic provides solutions to what's attacking the health of your plants. We provide plant and insect identification; nematode assays; diagnosis of injury from disease, insects, weeds, and chemicals; and help with nutrient-related issues.
Toddlers smiling with green plants

School & Community Garden Training

A garden is a classroom waiting to be explored. If you've ever wanted to start a school or community garden but were not sure where to start, the School and Community Gardens course is for you! This self-paced, research-based online class gives you the tools you need to teach youth to garden. Learn how to build a thriving, long-lasting school garden program of any size. Find more information or sign up for the class here!

Info Sheets

Keep these handy guides ready.
sign on white fence says compost happens

Compost 101

WHAT IS COMPOST? Compost is organic material made from food scraps and yard waste such as grass clippings. Compost is used to enrich soil as an alternative to traditional soil amendments such as fertilizer. It is safe to use on edible plants and can be made from material you already have. Composting organics takes this material out of the waste stream and transforms it into a valuable resource. Read more.
vegetables in a group

How to Grow Fruits and Vegetables

From backyards to apartment balconies, small-scale gardeners have plenty of room to grow fresh herbs, vegetables, and fruit at home. Basil, peppers, and even apples can successfully grow in containers, giving gardeners of all sizes access to fresh produce. Read more.
tomato turned upside down

Prevent Blossom End Rot

What is blossom end rot? Blossom end rot is the scourge of many gardeners. While commonly found on tomatoes, it can also affect peppers, eggplant, squash, and watermelons. Prevention is the only way to treat blossom end
rot. Once a fruit has blossom end rot, it is best to remove the fruit and discard it. More info here.

Have yard and gardening questions? Let us help.

The Master Gardener Horticulture Help Desk is a community service that Master Gardener programs provide nationwide. Help Desks in our counties open in the spring and close in the fall. Master Gardeners are volunteers trained by University of Illinois Extension educators. They may be present at their county Help Desks for you to come in and ask your questions and share your samples one-on-one. Or they are available to call with your questions. Master Gardener volunteers provide research-based answers to your home horticulture questions, such as:

  • Vegetable Gardening
  • Insect ID and Control
  • Trees & Small Fruits
  • Integrated Pest Management
  • Turfgrass Care
  • Flower Gardening
  • Plant Diseases
  • Tree & Shrub Care
  • Soils & Fertility
  • Plant Identification
  • and more!
Boone County Help Desk Info 2025

In-person hours: April 1 - September 30 | Monday - Thursday | Call the office (hours vary)

DeKalb County Help Desk Info 2025

In-person hours: April 14 - October 17 | Monday-Wednesday-Friday | 10 am - 12 pm

 

Ogle County Help Desk Info 2025

In-person hours: April-October | Call the office

Good Growing podcast episodes

Listen to the podcast episodes about horticulture, ecology, and design with Horticulture Educators Christopher Enroth and Ken Johnson.
Listen here

Gardening Blogs

Companion planting: Combining plants for a healthy, well-balanced garden | Good Growing

As we creep toward spring, many gardeners begin to get the urge to get out in the garden. Seed starting and garden planning activities are well underway. One gardening technique that many gardeners incorporate into their gardens is companion planting. Read more here.
Light pink orchid plant

Houseplants that Bloom | Flowers, Fruit, and Frass

While beautiful foliage is a common feature of many houseplants, we often reserve the vibrant blooms for outdoor gardens or patio containers. However, this isn't always necessary. With proper care, a variety of flowering plants can thrive indoors and even rebloom multiple times, adding a burst of color to your home or office.  Read more here.

 

Rotating crops for a more a resilient garden | Good Growing

As the growing season approaches, final plans are being made for home gardens. What to plant and where to plant are big questions that require multiple levels of consideration. What to plant requires an analysis of the intended use, what the growing space can support, and how the climate will impact production. Read more here.