Newly installed landscaping requires frequent watering. Smaller perennials and shrubs can dry out in one day when temperatures are hot. The amount and frequency of watering depends on the size of the plant(s), the time of year installed, the soil medium, type of mulch, and of course, the sun exposure. For accurate results, check the root ball with your finger before watering.
When plants are newly installed the surrounding soil may be wet but the root ball itself could be dry as the roots are not yet able to access the water in the soil outside of the root ball. The plant draws the water out of the root ball faster than it can be replaced. It is critical to feel the root ball, not the surrounding soil, when determining whether a plant needs water or not. One sign of drought is wilt but be careful because over watering over an extended period can lead to root rot which also results in the plant wilting. Rain schedule also has an impact on supplemental watering. If we receive less than ½” of rain don’t count out watering still. Wind will also affect your watering schedule as it dries out soils much quicker.
Newly bermed or roto-tilled beds with compost and peat amendments will drain better. Early on more frequent watering is recommended. As the plants develop a stronger root structure the need for frequent watering and adding of nutrients is reduced but not eliminated.
The mulch you choose will also impact your water schedule. Rock heats up and dries soils and plants faster. Bark mulch absorbs and conserves moisture, keeping soil temperatures cooler and reducing the need to water.
Lawn irrigation systems are designed to water your lawn, not your landscape beds. It is recommended to adjust your sprinkler heads to accomplish this. Frequent watering of your lawn and landscaping with your irrigation system actually promotes problems such as shallow root systems and the formation of molds and fungi. The best time to water your lawn is in the morning before the sun gets intense. Watering during the hottest portion of the day is not ideal as a great majority of the water evaporates before it reaches the ground. Watering of lawns, landscape beds and plants during the evening or overnight is not preferred as the water remains on the leafy part of the plant and increases the potential for molds.
Evergreens require special attention in the fall. This is a time of year when vegetative growth stops and plants use the energy they produced in the summer for root growth and energy storage for the long, dry winter. If the root structure is dry going into the winter, evergreens will not have enough moisture to survive the desiccating winds of winter. This means keeping at least one spigot on well into November, sometimes until Thanksgiving. Be careful to keep an eye on the evening temperatures. You may need to temporarily shut off the water, open the spigot but resume watering when the temps improve during the day. Remember to include in this watering any boxwood, rhododendrons and all of your other evergreens (plants that retain their needles and leaves year round). When fall watering (late OCT-Thanksgiving) a good soaking every 5-7 days should be adequate. Your deciduous plants and perennials would appreciate a good soaking in early November also but it is not as critical as with evergreens. Fall watering is especially important the first year of a planting but should be done annually as well.
Water using a gentle rain wand on your garden hose.
SPRING & FALL
Temperatures below 75degrees full sun Photo of a Gentle Rain watering wand.
Perennials, grasses, & small shrubs Every other day for 10-15 seconds
Medium shrubs Every other day for 45-60 seconds
Large shrubs, small trees Every 3-4 days for 1-1 ½ minutes
Medium to large trees Every 5-7 days for 5 minutes
Temperatures above 75 degrees full sun
Perennials, grasses, & small shrubs Every day for 10-15 seconds
Medium shrubs Every other day for 1 1/2 minute
Large shrubs, small trees Every 5 days for 5 minutes
Medium to large trees
These guidelines apply for the first 6-8 weeks following the installation. At the 6-week mark you should be able to begin weaning the plants by adding another day in between watering and reducing the amount of water given.
Into the second season plants have become established, again reducing the amount and frequency of manual watering. In the event of a rain shortage or drought however, it is beneficial for the plants to get a good soaking every 10-14 days.