I am hard pressed to remember an early July with a string of days over ninety degrees, and going on to push one hundred degrees.   For five days now, our weather has been blistering hot.  Of course every gardener’s attention turns to the well being of the plants, when the weather goes haywire.  The obvious medication for relentless heat-water.  OK, watering is essential, but informed watering puts your efforts where it counts.  Water does not solve every high temperature  issue.  Annual plants-they love the heat.  Most are native to tropical climates where high temperatures are the norm.  I have no idea off the bat where cosmos originate, but those needle like leaves mean they are drought tolerant.  Why is this?  Plants take up water, and the leaves sweat.  A plant with a minimal leaf square footage transpires slowly.  The giant leaved ligularias and butterburrs have enormous leaf surface; in the sun, or at the end of a hot day, their leaves are alarmingly droopy.  Don’t sound the SOS yet.  Heat makes all of us sweat.  But heat does not necessarily mean they need more water.  You can overwater plants, trying to cool them off. 

Rob has had a hose in his hand for the better part of a week.  Hot and dry conditions affect our trees, our container plantings, our boxwood-he waters.  The extreme heat-I am seeing him in a baseball cap for the first time in 18 years.  He looks like someone I never met-disconcerting. This astonishing tail end of June excruciatingly high heat makes the job of watering a critically important job.  People and plants alike suffer-proper hydration is key.  

This photograph taken in full sun does not much speak to heat.  White flowers look fresh, no matter the temperature.  The silver dichondra is waving to the right-your only visual clue that this 95 degree day was accompanied by a strong, drying breeze. Every plant in this old cistern is heat resistant.   The burgeoning datura centerpiece is immune to the high temperatures.  The thick leaves that transpire slowly-an ace in the hole.  Petunias-so drought resistant.  Euphorbia Diamond Frost-should you want to grow giant euphorbia, water sparingly.    

These ultra double white petunias grow long-it is their only fault.  Should you plant them with company that disguises their leggy arms-they shine. Never mind the withering heat. 

Lotus-they love the heat. Those giant leaves never wilt- why would they?  Submerged or just above the water’s surface every day, they look juicy no matter what the temperature.   Clients that have no time to water- a container stuffed with water loving plants and lots of water-this might be an idea worth pursuing.   

Junipers-even people who do not really garden know the word.  They thrive on neglect-meaning, the less water, the less of everything, the better.  Like the annual cosmos, their needle like foliage presents little surface area from which to transpire. 95 plus degrees-the junipers are unfazed.  Should you have really high heat, sort out what needs water, and what is wilting from heat.  If your trees and shrubs need water, soak thoroughly.        

The cirrus dusty miller-no one grows this plant but my grower-at my request. The large silver felted leaves are so much more beautiful than the serrated dusty miller-would you not agree? These large hairy leaves are heat resistant-but big leaves need your hose when the going gets tough. 

Phormiums-New Zealand phormiums-are immune to high temperatures and dry conditions.  This plant-I have had it for the better part of ten years.  I have never seen it wilt.  If you garden in intense heat and dry conditions, get some phormiums going on in your garden.  They look fresh and great, when it is one hundred degrees.   

Most tropical plants love the heat-this banana centerpiece is no exception. Should extreme heat be sweeping through your neighborhood, remove those leaves at the soil level that threaten to rot. Encourage good air circulation. Clean culture is a good idea.  I water the surface of the soil-and not the leaves.  Heat and water provide an ideal climate for mildew and other fungal infections.  Just like you, I have the idea to put as much as I can to a distress call; this weather makes me want to shower everything with cool water.   I have desperation watered plenty of times.  Should you get a garden SOS, think before you act.    

Late day comes, sooner or later.  What you were sure would flop over and expire lives to see another day.   

It is appallingly hot-no gardener in my region questions this. Nature-she has a way of making everything in a garden a challenge.  My annual plants are loving this heat, and growing like crazy.  Keeping them watered is like adding a part time job when I already work full time. But when I look at my plants, all in all I like what I see.


  1. I only remember one summer where we had such continuous high temps, and that was late July/early August (I think) in the latter 1980’s. I think we had four days of 94+ and everyone thought it was freaky. I was living in Brighton, Mi at the time.

    Love your post on the hot ones!

    I too like that dusty miller. There’s a big leaved culinary sage that I like, too. More green to it’s leaf and a great texture.

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