Heat Zones, Plant Health, and the AHS Heat Zone Map

With tools like the USDA plant hardiness map, we typically only consider low winter temperatures as the primary metric by which we determine which plants to sow. However, we might benefit from incorporating summer temperature trends, like the information presented in the American Horticultural Society’s heat zone map, into our planting decisions. With summer temperatures spiking to record highs due to a changing climate, the impact of high heat on plant life is becoming increasingly relevant to growers.
U.S. map showing colored heat zones

Summer Evening Hours!

The Garden will be open until 8 p.m. on the third Thursdays in June, July, and August 2024. The Garden will stay open until 8 p.m. on June 20, July 18, and August 15, 2024, for visitors to enjoy the golden hour and sunset amidst summer flowers and the USBG plant collection from around the world. Lemonade, botanical non-alcoholic mocktails, and snacks will be available for purchase. Learn more
Two young women look at tropical plants in the U.S. Botanic Garden Conservatory

Frostbitten Flora - What Happens To Plant Cells When It Freezes?

Even with spring quickly overtaking winter in the Mid-Atlantic, many gardeners are still monitoring frost dates. An unexpected late freeze could have detrimental effects on spring plantings. Freezing temperatures present a specific set of challenges to flora that can only be understood when seen at the cellular level. It can cause damage or fully kill a plant. So what happens to a plant’s cells when the temperature falls below freezing?
electron microscope image showing plant cells before and after freeze damage

Poinsettias flourish at U.S. Botanic Garden

The gardeners have grown almost 2,000 poinsettia plants to brighten up the United States Botanic Garden Conservatory's annual holiday exhibit "Season's Greenings." An expert team at USBG cares for the annual poinsettia crop with daily attentiveness starting in July.
a bed of red and white poinsettias

U.S. Botanic Garden Taps New Technologies To Grow Plant Education

The Learning and Engagement team has embraced new technology and instructional approaches to successfully offer more than 200 programs online, engaging more than 17,500 participants from all 50 states and 27 countries. The team has also developed live virtual field trips for schools, engaging more than 4,000 students from throughout the D.C. area and from states ranging from Florida to Maine.
Grace Anderson adjusts the camera and laptop for an online horticultural education program.