Penn State Master Gardeners of Mercer County

03/05/2026

Despite all our posts being set to "public", it seems the share button isn't always available. Apparently this is a glitch that is happening to pages with some of their posts. The work around currently supplied is to click the 3 dots on top right of post and use the copy link feature. This method typically only shows a link url so you may want to add text to your post so people know what the link is about.

03/05/2026

You are running out of time to register for this weekend's pruning event! Deadline is tomorrow, March 6th 11:45pm. This is a ‘learn-by-doing’ workshop. The goal is for you to feel comfortable either pruning your own trees and shrubs or overseeing/directing someone else doing the work.
We will meet at the Penn State Extension-Mercer County Office located on Route 19 N, 463 N. Perry Highway, Mercer, PA. The ‘walkabout’ will be on the Extension Grounds. In the event of storms, there will be a demo inside.
You will learn:
• How to choose the right tools for the job
• When to prune – and why
• What to remove/what to keep
• How to cut both small & large branches
• What NOT to do
• How to stay safe!
More details on our event page.
"Pruning Made Easy"

Hands-on workshop teaching proper pruning techniques for trees and shrubs, building confidence to prune safely or supervise others.

03/05/2026

You are running out of time to register for this weekend's pruning event!
Deadline is tomorrow, March 6th 11:45pm. This is a ‘learn-by-doing’ workshop. The goal is for you to feel comfortable either pruning your own trees and shrubs or overseeing/directing someone else doing the work.
We will meet at the Penn State Extension-Mercer County Office located on Route 19 N, 463 N. Perry Highway, Mercer, PA. The ‘walkabout’ will be on the Extension Grounds. In the event of storms, there will be a demo inside.
You will learn:
• How to choose the right tools for the job
• When to prune – and why
• What to remove/what to keep
• How to cut both small & large branches
• What NOT to do
• How to stay safe!
More details on our event page.
"Pruning Made Easy"

Hands-on workshop teaching proper pruning techniques for trees and shrubs, building confidence to prune safely or supervise others.

03/01/2026

Reminder if you are tracking Growing Degree Days, it typically starts March 1st. Here is a link to how to use the calculator tool Cornell provides:

Watch this video to learn how to use the Cornell CSF Growing Degree Day Calculator, which is part of the suite of Climate Smart Farming agricultural decision...

02/27/2026

If you have decided to incorporate growing degree days to control pests in your garden, you can calculate on your own using this information from Penn State's Tilva:
The basic formula involves taking the average of the daily high and low temperatures: (High Temperature + Low Temperature) / 2.
From this average, a specific ""base temperature"" for the crop or pest is subtracted. This base temperature is the minimum temperature required for development to occur.
If the calculated GDD value is zero or negative, it is recorded as zero, as no growth occurs below the base temperature.

Some calculations also include an upper temperature cutoff, where temperatures above a certain point (e.g., 86°F for corn) do not further increase growth rates.

If you don't want to calculate on your own, another option is to use the calculator from Cornell University at https://climatesmartfarming.org/tools/csf-growing-degree-day-calculator/ There is information on that page that explains how to use the website.

This map shows the accumulation of base 50°F growing degree days (GDD) from March 15 to the current date. This map is a product of the Northeast Regional Climate Center, and part of a set of GDD Maps developed for the turf grass industry.

02/27/2026

Invasive plants = bad news for wildlife! 🚨

These aggressive invaders outgrow, outspread, and outcompete native plants, taking over habitats and disrupting the food chain. Here are five invasive plants to avoid (and help remove)!

Learn more: https://www.pa.gov/agencies/dcnr/conservation/wild-plants/invasive-plants

02/26/2026

Cornell University discusses how using growing degree days can help with pest control.

Does weather factor into your landscape pest management decisions? Keeping track of weather, and specifically daily temperatures, can help you fine tune the timing of pest management activities, contributing to significant savings in costs of labor, materials, and plant injury.

02/25/2026

Are you intrigued about growing degree days? University of Maryland extension provides an extensive article on defining what it is and how to use it.

Degree Days (DD), also termed Growing Degree Days (GDD), measure how much warmth above a certain threshold has accumulated since the beginning of the year.

02/24/2026

It's not to early to be thinking about garden pests.

One of the means for pest management is monitoring growing degree days. Penn State's Tilva defines growing degree days as "Growing Degree Days (GDD), also known as heat units, are a calculation based on daily air temperatures used to estimate the growth and development of crops and pests. This method is generally more accurate than relying on calendar dates because it accounts for variations in weather conditions each year, which directly impact physiological development.

GDDs are a valuable tool in integrated pest management (IPM) programs for predicting insect activity and timing control measures, as well as for forecasting crop growth stages and maturity."

Check back over the next few days for more information on how to incorporate GDD into your gardening.

02/23/2026

Exciting news! The invasive replace-ive program is returning this year!

Due to strong public interest in the inaugural 2025 start and continued successful statewide collaboration, the PA Invasive Replace‑ive Program will return in 2026 with additional sites.