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Help your trees with watering bags

By July 22, 2017 No Comments

It’s very hot in our July British Columbia landscapes and plants need help. Trees are plants so let’s help them with some supplemental water. One great invention is the Gator watering bag.



A Gator watering bag in action. They work best when they are filled with water. Full marks to this dedicated home owner.



Installation and benefits

You don’t need any tools to install the bag. Just put the bag around your tree and zip it up. Then add water. The slit is located under the label tag. Once, when I was working for the City of Coquitlam, an elderly couple walked by and wondered how we get water into the bags. Just lift the tag.

The Gator website states that new plantings require a refill every 5-7 days. The average watering time is 5-9 hours. And the benefits? No run-off and limited evaporation.

You can use the bags to protect young trees which should limit losses and labour costs associated with tree planting. That said, some young trees still don’t survive. Perhaps they weren’t planted properly or came from inferior nursery stock.

Not so fast

It would be great if this was the end of the story. Bags go around the tree trunk and deliver much needed water boost to thirsty trees. Not so fast. Just last week I visited my favourite blog called the garden professors. It’s a special blog because people try to use good science to answer questions.

One post that appeared on the blog site was about Gator bags. The author noticed two problems:

a) Many watering bags were empty!? Since the bags were designed to deliver water to trees they should be filled with water. Obviously.

b) A bigger problem was unzipping the bags and discovering bark rot. As the full bags press against the tree trunk they create moist and dark environment and, over time, this can lead to bark rot. Rotting bark then invites diseases and pests.

So I did my own survey on a large site we maintain. I found one tree with a moist bark section; some had bugs hiding under the zipper.



All clear. The bark was dry and, alas, so was the bag.



Same as above.


Think of the Gator watering bags as a temporary solution. Install them, fill them up and check on the condition of the bark periodically by unzipping the bag. I hope your trees get through the summer heat without injury.

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