How to Water
Thoroughly, deeply, and slowly, as needed - rather than shallowly. For example, a new shrub needs at least three gallons of water directly to its root zone after planting. Watering it at just the surface will do more harm than good, causing roots to grow close to the surface. Use the “drench” setting on your hose nozzle, or remove the nozzle and just point the hose end around the base of the plant. Soak the soil to a depth of 4 inches.
Plants that are bought or moved in the spring or summer need serious coddling until their first winter just to keep from them dying in the heat and drought. (What may seem counter-intuitive is that it’s not the cold that kills plants, but heat and lack of water.) Other plants that need frequent watering are those in containers, and most annuals. Most garden plants, especially if they're chosen for drought tolerance, require supplemental watering only during long droughts.
One more exception? Plants located under roof overhangs where rain can’t reach them, and we forget to water them when rain is plentiful. So just like pots sitting on porches under the roof, plants situated under overhangs anywhere need attention no matter how much it's raining.
Careful with New Plants!
- When plants are put in the ground in the late spring or any time during the summer, it’s a huge challenge to keep them alive through that first season because their roots can’t handle heat and drought yet. (In their second season you can relax about it, or if you plant in the fall.)
- Small plants like perenn ials need watering at planting, then again the next day, then 3 days later, then weekly throughout their first summer. Larger plants like trees need that first deep watering, then again in 3 days, then weekly for a month and twice a month for the remainder of their first season. These guidelines assume the lack of long rains, of course.
- Most “drought-tolerant” new plants still need to be coddled their first season.
- When planting shrubs and trees in the fall, be careful not to overwater — it’s the most common cause of their early demise. Their roots aren’t developed yet, so just soak them thoroughly after planting, apply mulch, and don’t water again for a week.
Plants in containers need to be watered far more often - usually every day and in really hot periods, even twice a day. (Depending on the plants, of course. Succulents are a great choice for containers that don't need much attention.) After years of filling and carrying watering cans out to my deck, where most of my containers are located, I finally had a hole drilled in the deck for threading the hose from the spigot below and voila - watering is suddenly easy!
- Automatic irrigation systems, though expensive, are great if you travel, but don't let it be so automatic that you stop going into the garden to observe what’s going on with your plants.
- Soaker hoses are much less expensive and with timers attached, they’re a low-maintenance solution that uses waste efficiently. They only work well on flat surfaces and over short distances, though.
- Overhead sprinklers are usually used for lawns and Bob Peterson, Behnkes' manager of supplies, thinks the Ray Padula brand gives the most even coverage. For mixed beds, sprinklers usually need to be supplemented with hand watering to reach plants behind taller plants. .
- One technique that works well for trees is a slow drip from the end of a hose. And by slow I mean for a couple of hours, at least. (Some experts say a minimum of three.) If the water is running off, decrease the flow. If there’s an incline, leave the hose uphill from the tree. No need to move the hose around; it’ll penetrate the area if allowed to run long enough.
- Hand watering, while time-consuming, is the method of choice by die-hard gardeners like myself. (Washington Post writer Adrian Higgins says there’s a “Zen-like quality to it,” and I agree.) Use a good multi-setting nozzles or a wand - the ones from Dramm seem to be everyone's favorites. (And a reminder from Bob Peterson about hand-watering - don't use it for your lawn!)
More Watering Tips
- Save time and possibly your plants by grouping the ones that need frequent watering.
- If you're moving hoses around the garden, hose guides can save plants from decapitation.
- Remember watering isn't something that can be done by the calendar. It takes observing the weather or checking the soil to know when your plants need supplemental watering.