Picture a planter in the middle of a heat wave: full sun overhead, hot pavement below, and no water source for blocks. By every rule of gardening, these are very challenging conditions. Yet our plantings hold their color through the hot NYC summer. So how do they make it through? Along with the dedication of our crew who work all year, in all conditions, The Hort has strategies to make our plantings heat-resilient.
The most important factor is timing. This year we moved our perennial plantings up into April, while temperatures were still cool. Plants that settle in during cool weather build strong root systems, so they’re ready by the time the summer heat arrives. The difference showed: our early perennial containers have done beautifully, while some later annuals had a harder start. Next year we’re aiming to plant even earlier, since a stretch of 100-degree days is hard on any young plant still getting established.
Plant choice matters, too. Rather than fill every site with the same few tough species, we balance dependable performers like coleus and begonias, which handle sun, shade, and drought, alongside plants that add color and feed pollinators, like cuphea. Some of these are trickier to establish, which is one more reason to plant early and water well.
Water is another challenge that requires a nimble crew and innovation. At Fordham Plaza, we’re trialing superabsorbent polymer crystals mixed a few inches into the soil, where they swell when watered and hold moisture near the roots. We’ll share how they perform as the season goes on. Self-watering inserts, sustainably installed last year, create a hidden reservoir inside planters so plants can keep drinking between visits.
Creating more shaded areas is a bigger and longer-term strategy to cool our city and ease summer’s strain on plants (and people). The Hort is proud to be on the Leadership Team of Forest for All NYC, and we are working alongside the coalition and other partners to reach the city’s goal of growing tree canopy to 30% by 2035, and more shade for everyone. Trees cool the streets beneath them, clean the air, and make everyday routes more comfortable. Neighborhoods with the least canopy today feel the heat most, but every tree planted now is relief for summers to come.
The Hort aims to make horticulture a reality for every neighborhood, which usually means working in the in-between spaces of our daily life, like streetscapes, plazas, and medians, where the effects of summer are harshest. Here we plant thousands of containers and tree pits. Keeping these plants alive through August is both the work and the test of our mission.