We love this lovely sunny weather –blue skies and crisp air. However, for each day it is sunny, your plants go another day without water. The Boston area hasn’t had more than an inch or two of appreciable rainfall in the past two and a half months, when we usually get 6 – 8 inches. We’re in a dry spell which can spell disaster for your plants going into the winter. Even those of you with irrigation systems will have plants that are in distress since irrigation systems rarely offer enough water volume to the larger plants in your landscape.
ROOT DEVELOPMENT: Fall is the time when perennials, shrubs and trees hunker down and stop growing above the ground: leaves fall off, stems dry, needles shed. All seems quiet and dormant. But if we could look under the ground, we would see an active bevy of root development happening. Soil temperatures are still warm, and plants produce more new roots in the fall than in the spring until the ground truly freezes. This is why planting in the fall is so successful: we take advantage of a plant’s natural inclination to develop new roots. A strong root system helps plants be ready to start growing right away in the spring.
HYDRATION: Even though plants stop producing growth above ground, their leaves continue to transpire water. Picture your rhododendrons and boxwoods that keep their evergreen leaves into the winter. They are still losing water molecules from their leaves each day without being able to bring in new water from the soil. This leads to leaf desiccation over the fall and winter. The leaves turn yellow and dry up. In addition, water stress can prematurely cause fall coloration.
GARDEN INSPECTION: Our advice is to go out and look at your plants – do you see any drooping leaves, yellowing, brown curled edges, or wilting? These are signs that your plant is stressed with the lack of water. I encourage you to also look at your larger shrubs and trees.
DEEP WATERING: We recommend deep watering to get moisture down into the top 18” of soil where the majority of water-absorbing roots are found. The ideal method is the slow-soak method – put your hose at the base of the plant and turn on a low trickle from your hose for 1 hour per plant. Keep track with a kitchen timer so you don’t forget and leave the hose running. If you are fortunate enough to have a sprinkler system, use it! An adequate amount of water would be 1-2” of water every 4-7 days, if we continue to have little or no rainfall.
Prioritize your newer plants since they are still establishing deep root systems and depend on surface water for survival. But with this drought, also deep water any tree with a trunk 2-5” wide and larger, older shrubs.