Saturday, July 9, 2011

Cool nights in the garden

Our greenhouse
Our latitude here is 52 N and our altitude is 2750' above sea level.  We get lots of long, warm days but our nights stay cool.  A typical mid-summer day can start out at 5 C (note the Canadian way that I mix metric and imperial?), go up to 30 C or more, then end up back at 5 C.  This creates wonderful conditions for people and animals who are happy in the daytime heat yet sleep comfortably.  It's also great for cool-weather crops like peas and lettuce, but it makes the heat-loving crops a challenge to grow.

Peas in the garden
Tomatoes, for example, stop growing below 12 C.  In our brief, 90-day frost-free season, we might only get half a dozen nights above that temperature all summer.  Even in our greenhouse (which is unheated), the tomatoes grow so slowly that the fruit hardly starts to ripen before we're heading into the autumn's frosty nights.  I don't try to grow our full supply of tomatoes but just put in a few plants for treats to snack on.

This year, the weather has been so cool that I don't know if any tomatoes at all will ripen!

Knee-high tomatoes in the greenhouse

1 comment:

  1. Try surrounding your tomatoes with bricks or old 4l milk jugs painted black and filled with water. It helps to hold the heat from the day a little longer. I put bricks around mine this spring and covered them all (with mini-greenhouses)until they started flowering and it helped a lot eventhough our daytime temps were barely cracking 14c - I actually have a few tomatoes on the plants. This is amazing since it wasn't even really warm until the end of June - over 20c.