A Letter From Paul Larson, 8.31.15

“As far as the weather is concerned, I guess it’s true that no two years are exactly alike. However, one thing that does seem to be consistent from year to year is the occurrence of a prolonged dry spell sometime in mid-July to late August. While I know some other areas of southern New England have had some much-needed rains in the past couple of weeks, here in northeastern Connecticut we are in a rather serious water deficit right now.

I know that the vast majority of gardeners are aware that when you plant a tree or shrub in the summer months, you need to stay on top of the water needs of your new plants and try your best to avoid the stress caused by too little water. The real reason for writing this note today is to remind people that almost all plants that were installed this year, even if they were planted back in April or May, will need some supplemental watering in these dry summer weeks.

A typical shrub, for instance, that you purchased back in the spring and planted in your landscape has had some time to establish new roots in its new home. That root development is probably 2-5 inches beyond the original root ball by now. While it may appear to be doing well despite the lack of rainfall, its ability to absorb water from the soil is still limited to the small area immediately around the root ball. Too much stress caused by lack of water now can lead to stem die-back, poor flower bud development for next season, and even winter kill over the coming winter.

Often when a plant does not survive its first winter, the cause can be traced back to drought or other stress the plant was subjected to during the previous summer. Some plants will wilt when they are too dry, with leaves hanging down and looking rather sad. Plants such as hydrangeas and other deciduous shrubs and most perennials with “tell you” when they need water; the foliage will wilt and hang from the stems. Other plants, especially needle-leaf evergreens, don’t have a wilting response to drought. They just sit there and suffer silently, until it can be too late – they are too far gone to recover. Premature yellowing of the foliage and even leaf drop is another indication of drought stress.

So, what to do? The key to getting your landscape, and especially the newer additions to your gardens, through this dry period is giving them adequate and thorough supplemental watering. While soil types will vary somewhat and individual plant needs are different, a general rule would be to provide deep, thorough watering every 3-4 days. You should apply small amounts of water over a long period so the water has time to soak deep into the soil and completely wet the root zone, similar to a gentle soaking rain.  Sprinklers can do this, but you often lose quite a bit of water to evaporation with this method, and you often end up watering a larger area than is needed.

Here are a few options for effectively watering your plants:

  • Soaker Hose – A soaker hose on a timer can be very effective and slowly delivers the water right where it’s needed.
  • Drip Pail – For individual plants, especially when your garden hose won’t reach the new tree you planted at the end of your driveway or some other location away from the house, I would recommend using a five gallon pail with a 1/8” hole drilled on the side just above the bottom of the pail. Fill a second pail with water, and take both pails to the plant to be watered. Position the pail with the drilled hole right next to the base of the plant and fill it with water. It can take about 20 minutes for a full pail to drain through that small hole, and the water is going to slowly soak deep into the root zone, right where it will benefit the plant the most.
  • Drip Hose – Another method is to turn on your hose so you are getting just a slow, steady drip of water. Place the end of the hose at the base of your plant and let it run for 2-3 hours. In that time, you’ll soak the root ball and the soil surrounding it, and the plant should be fine for 3-4 days, even in this hot summer weather. One note of concern here is that you should not do this in the mid-day hours. With very little water flowing though the hose, the sun can heat up the water temperature to over 100 degrees. Your plants need water, but not hot water! Set up your hose like this in the early morning or late afternoon, and you can easily water several plants with very little effort. (I like to set the alarm on my cell phone to remind me to move the hose or turn it off.)

Using one of these methods, you can help your plants make it through these hot summer periods and you’re giving your plants an important advantage to survive our New England winters. They will reward you with more flowers and berries, colorful fall foliage, and more vigorous growth next summer. Happy gardening!”