Home & Garden

In search of the right amount of water

The first week of August means it is time to face your water worries. It’s been unusually hot, and there are more hot, dry days ahead, so commit now to some irrigation insurance so you won’t loose valuable trees and shrubs.

If your concern over your water bill is stronger than your love of a green lawn, then let the lawn go dormant or “golden” for the rest of the summer (if it hasn’t already). Lawns that dry out in the summer are not dead. The grass will spring back to life and green up in the fall once the rains begin again.

The plants that will need extra water this month are thirsty rhododendrons, azaleas, camellias, blueberries and any tree or shrub planted within the last year. The rest of your landscape, including trees and shrubs, will appreciate a good soaking at least once a week – but how much water they need depends on your soil, your mulch and how much it rains. Use a hand trowel to dig into the soil near your shrubs. Check the color of your soil 6 inches below ground level. If the soil is dry and light in color, either do a rain dance or offer everyone a drink.

Watering questions must be heating up the dinner table discussions. Here’s my vote on family debates and intervention when it comes to drinking problems in the garden.

To keep our lawn green, my husband wants to have our automatic sprinkler system come on every single day. I say that is too much. What is the right time to turn on the lawn sprinklers, and how long should they run? – J.K., Tacoma

There is no easy answer for this one, but watering your lawn every day is too often. The fungus among us – such as Red Thread – will attack a lawn that is constantly moist. Watering every day also is a waste of a valuable resource and drives up the water bill.

Ideally, your lawn will stay green with just 1 inch of water a week – and that 1 inch should be applied slowly so the water has a chance to soak into the soil and applied once or maybe twice a week.

Set out an empty tuna can to measure how long it takes your sprinkler system to fill the can with 1 inch of water.

If your lawn needs more water than that to stay green, take steps to improve those thirsty grass roots by aerating the soil and top-dressing with an inch of compost.

Getting compost down into the soil will act like a sponge to hold more moisture.

You also can save money on your water bill by adding a “rain sensor” to your sprinkler system. These are inexpensive devices that note when rain is falling and then automatically turn off your sprinkler system.

Check your home center store or irrigation supply center for a rain sensor.

To wean your lawn from its daily drinking problem, reset the sprinklers now to come on every other day. Gradually taper off on how frequently you water as the soil improves and the weather cools.

Can I overwater my hanging baskets? I water every morning but notice the petunias in my hanging baskets are wilting and turning yellow. My neighbor said they are drowning from too much water! Is this possible? – P.P., Olympia

Yes, many plants in pots suffer from too much water, and you could be forcing your petunias to drown in misery.

Good drainage is crucial during hot weather when you water often. Sometimes, by mid-summer, the drainage holes of hanging baskets and pots become plugged up with roots or blocked by the weight of the pot and the stagnant water trapped inside causes root rot. Poor drainage causes root rot, and the plants will wilt as their root system shuts down.

Petunias are the canaries of poor drainage, singing the blues if they have to endure wet feet or soggy bottoms. Slip bottle caps or pieces of tile under the edges of heavy pots to serve as pot feet that will increase drainage. Use a sharp knife to poke into the drainage hole and loosen any roots that might clog the opening of your hanging baskets.

Most importantly, feel the soil before you water your plants. Don’t offer a drink until the top 1 inch of soil in the container is dry to the touch.

Help! In the recent heat wave, my hanging fuchsia basket got a bit overheated. All of the petals dropped from the flowers and the leaves started to wilt. I realize now that I need to water more often. Can I save this plant? Will it recover? Is there first aid or CPR for dry fuchsia baskets? – M.R., e-mail

Time to reduce, rehydrate and recover your wilted plants. Flowers that normally thrive in our cool summer weather – hanging fuchsia baskets, lobelia, begonias and impatiens – are struggling with the heat.

They will pout, wilt and throw a fit when temperatures break 85 degrees. (Tomatoes, geraniums and most herbs love the hot weather.)

If wilted plants don’t perk right up after a good drink, you’ll need to take drastic measures.

Reduce the size of these heat-shocked plants by cutting them back by up to one half. Pruning always stimulates growth and this jolts them out of their stupor.

Then rehydrate with extra water, submerging the entire hanging basket under water if the soil has become hard-packed and sheds water.

Use a water-soluble plant food such as Miracle-Gro or Alaska fish fertilizer to force feed some new life.

Your pruned fuchsia will pump out new shoots with a whole new attitude. Either that, or it will stay wilted to let you know it’s ready for the compost pile.

Marianne Binetti has a degree in horticulture from Washington State University and is the author of several books. For gardening questions, write to her at P.O. Box 872, Enumclaw, WA 98022. Please send a SASE for a personal reply. She also can be reached at her Web site, www.binettigarden.com.