Archive for plant stress in heat

Hydrangea Love

Designers mom with  favorite hydrangea

My Mom with Oliver, the Hydrangea

Hydrangea Love

There are several lessons in this story for you, O gentle reader………..how to successfully transplant a shrub or tree in July heat……, how to prevent hot weather damage to your plants when we have intense hot weather right on top of weeks of cool rain, (more critical if you agreed to have your garden on a fundraiser tour).  This will also work to restore plants in a container that you forgot to water???? ……………..these helpful lessons all fit into this story.

The story:  My mom and dad planted and named the two hydrangea by the back patio, Mary and Oliver.  Mary was beautiful no matter what but Oliver had troubles.  Every year in early summer, Oliver’s flowers would get crisped.  If they had planted Oliver a few feet closer to the covered patio there would be no problem and no story.   They planted Mary in the afternoon shade of the patio but Oliver got the early afternoon sun in June and July. He was just not a super sun tolerant kind of guy.

He could handle the sun better once the leaves and petals had hardened off in July but in early June, while the leaves and petals were full of spring, freshly unfurled, a 100 degree day or two would toast all the new flowers on the plant.  So Oliver’s flowers would scorch and my parents would then over water Oliver trying to get some water back into his petals. They did not understand that once petals are scorched they stay that way. Oliver’s new flowers were fine but now the plant’s leaves looked terrible. Over watering caused the leaves to wilt and yellow. Oliver was a mess.  I offered to come over and protect Oliver from them. The human Mary and Oliver had long since gone on so these were not really plants to my parents, but symbols of their dear friends.

Protecting plants from heat stress in Portland Area Landscape Design

The Sheet Trick

So how did I do this?  The Sheet Trick!  My first solution was to water once a week and the second solution was to protect Oliver from intense sun.  My solution was time consuming mostly because I lived in NW Portland and my parents lived in Gladstone.  If I was expecting intense sun,  I would drive over, get out some binder clips, drape a white sheet over Oliver to cover all his leaves and flowers and then clip the sheet onto various large stems so it could not blow off.

Because the leaves were covered (this is science folks!) they held in the water rather than letting it go, this is called transpiration. Transpiration is part of the plants photosynthesis process with the sun.  See Wikipedia on photosynthesis.  Since the flower petals and leaves kept their water, they stayed cool enough and did not scorch. I would not leave the sheet on for more three days at a time so I didn’t have to go over there every single day, just when I knew it was going to be hot.

Hydrangea PistachioWhat’s important for you gentle reader is that this sheet trick is handy beyond belief for all kinds of things.  Number 1  best tip ever for transplanting a shrub in the summer…….keep it covered for 3 days and I mean immediately or even during the digging of the plant if you are feeling compulsive.  Use it to protect flowering plants if we have intense heat while the flower petals are still new and soft. Use this trick if you have had an irrigation boo boo and your plants in one area didn’t get any water and  have wilted.  Presto, sprinkle the leaves with water gently, water the plant and cover for a few days……..your plant will have a better chance of recovery.

Every generation loves hydrangeas, my parents loved theirs, I love them although confess I have none of my own down here on the floating river house, my step daughters would love to have them…..maybe I can fix that this year.  They also look mighty fine with ornamental grasses so not just for an old fashioned garden but could be used in more modern gardens if placed thoughtfully.