As I was pumping water from my rain-barrel to water my hoyas this morning, I was thinking this is not something I would appreciate and I am sure they do not either. The outside temperatures were just above 32°F so the water had be just above that since I do hang a 100W aquarium heater in the barrel. I have continued using rain water to irrigate the hoyas inside the sun room even as the days got shorter and the temperatures dropped significantly. I have no noticeable changes to report and I feel very lucky about that. The plants continue to thrive in their warm cozy room which stays at or about 73°F day and night with the aid of grow lights and two heat humps which hang on the wall.
When the hoyas had all been hydrated I decided to post on Facebook the question of using cold versus warm water to water in and also mist the hoyas. I felt certain some of the Hoya Experts would have opinions and maybe even offer solutions to my dilemma. Sure enough within minutes I had a unanimous consensus that I should always water hoyas with warm water if possible. I was surprised though that nobody offered any reasons to back up their position but decided to find a remedy to continue to use the rain water to irrigate and mist the plants. Since I have the pump, hose and barrel in place for summer and altered a bit for winter I was determined to utilize mother nature throughout the year.
A great idea came from a hoya grower/collector in Tennessee where it gets quite cold but probably not for as long as it does here in my neck of the woods. She suggested adding an aquarium heater to the barrel and continue to use as always. After doing a few calculations and researching a bit on the internet, I decided to call a business that offers/sells aquarium heaters and have them give their expert opinion which would save me time and the aggravation of speculating. After a few minutes on the phone with the expert, he decided I should purchase 2-300W heaters to dangle in the barrel and the water should easily stay at the temperature of my choice all year round. Also, adding a small pump for circulation would assist but I am not sure if I will do that yet since that means one more electrical connection I will have to maintain out in the elements of rain, snow sleet and cold.
I am hoping that this is the final hurdle I must cross in order to conduct business as usual through these cold cold wet snowy grey days in PA. I surely have no experience growing or even living in these conditions but I am quickly adapting. The hoyas seem as happy and as healthy as they can be so life is good here in the Northeast!
UPDATE January 18, 2014 – After installing the two 30oW aquarium heaters into my rain barrel as well as positioning an insulator on the top opening I have success! The overnight temperatures were in the 20s and the water I used this morning to water the hoyas was about 88°F. I was hoping to also position a small pump on the bottom to circulate the water for better warmth distribution, but not sure I should since I run the barrel dry quite often. Nothing that a firm shake and maybe a stir cannot accomplish.