Water is necessary to grow roses—but too much and too little will kill them.
The key to the health of roses is knowing how and when to water them. Water transports nutrients throughout the plant: up through canes to feed new blooms and downwards to nourish and develop the root system.
But roses do not thrive when they are out of balance with water. Water escapes through infinitesimal pores on leaves through a process of transpiration. When roots are unable to replace lost water, wilting occurs. Too much water drowns roots by depriving them of oxygen, causing lower leaves to yellow and fall.
How Often to Water Roses
Water the roses with 1–2 inches of water weekly in a deep one-time soaking from early spring through fall. Water 3–4 days during extreme heat and dry spells. Highly porous soils need more deep, frequent watering.
Water deeply—16 to 18 inches below the surface. Shallow watering prevents roots from growing deep, making plants more vulnerable to injury and fertilizer burn.
Delivering Water Effectively
Test to ensure water is reaching the roots by checking soil moisture following watering. If water only reaches 8 inches, increase watering duration.
Choose the best watering method for your garden: drip irrigation, underground sprinklers, or hand watering.
Low-volume or drip irrigation provides water to roots efficiently with no runoff. Utilize emitters, drip collars, or perforated tubing.
Conventional spray heads are capable of wetting leaves and controlling spider mites, but mini-sprays conserve water and will not wet leaves well.
For watering by hand, a bubbler tip or basin on the ground around the plant is helpful. Water seeps into the soil slowly and does not erode the soil or splash mulch. Apply a 2–4 inch layer of mulch to reduce evaporation and prevent freeze-thaw cycles that cause root « heaving. »
Roses in Containers
Container roses need to be watered more often than in-ground roses since the soil is finite.
Check moisture levels daily or every other day in summer and daily if it’s hot or breezy. Unglazed pots lose moisture faster than glazed or plastic ones. To stop evaporation, nest a container inside another—just be sure the outside one has drainage holes.
By watering deeply, applying mulch, and selecting the right delivery method, you’ll help your roses grow strong, bloom beautifully, and resist disease.
