Thursday, May 17, 2007

Frost Watch 2007 - Day 3, problem

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Peppers inside polytunnel * more at bottom *

Conversation with friend over for supper:

Friend: I hear there is a possibility of frost.

Me: Really?
Looking outside at cloudy sky and remembering that it is only supposed to go down to 4C

Friend: Well I heard it on the radio, maybe it's changed.

Me: Huh, be right back.
Staring at pessimistic weather report by environment Canada:

" Cloudy. 30 percent chance of showers early this evening. Clearing near midnight. Low plus 1 with patchy frost. "

Me: Thanks, I think I have to go outside for a minute.

Hubby gives me that look.

Me: I'll be right back.
Quickly, I throw winter blanket back inside of polytunnel.

Problem is that it is already clear at 10pm but 6C!

According to optimistic forcaster, the Weather Network:

Humidity 100%, Conditions Clear, low 4C.

However, the dewpoint is 1 and the humidity, currently, is 70%.

Who is right, time will tell.

And since I'm writing this, time for another frost fact:

The reason why people use water to keep crops from freezing either by using a sprinkler, wall of water or other device is not so much because the water traps heat and releases it during the night but because cooling, especially freezing water releases heat.

Same thing?

Not exactly. When you freeze water, in other words, change its state of matter, the forming of bonds causes heat to be released. This is why ice forming will warm the area nearby.

Irrigation causes the formation of ice which helps prevent crop damage.

Counterintuitive but true according to my research.

To that end, I have placed pop bottles in my polytunnel. More on that tomorrow, if the plants survive.

---

*
The ground has been pre-warmed with clear plastic mulch.
Sticks are being used to support the winter blanket I am using as a 'row cover'
Pop bottles 3/4 filled with water and bricks are being used to store heat but see above about why water is used to prevent frost.
Peppers slightly squashed because I didn't use the sticks the first night with the winter blanket.

4 comments:

Anonymous said...

Hi Telsing,

I'm so glad that you have the patience to deal with row covers and blankets! I hope your plants survived the night. I took all mine in except for four test buttercrunch plants which looked pretty dismal this morning. When are you putting your tomatoes in?

Kathy

Anonymous said...

Isn't the weather annoying? We have some tomatoes in the ground too, some under the hoop house, some that we've just been covering over every night. So far so good, but we are going away this weekend and have to decide whether to leave them covered to possibly suffocate, or leave them uncovered to possibly freeze to death. Here's hoping the frost doesn't come. My plants are getting overgrown too.

Ottawa Gardener said...

Kathy: More than half are already in the ground under the polytunnel with the peppers and eggplants.

Garden Gremlin: Tell me about it! I hate going away during this time of year.

Unknown said...

Oh no... you said eggplants and my heart stopped. I have been bringing my annuals (as yet unplanted) inside but forgot that I'd already planted eggplants in the back. :( I had found 'Ichiban' eggplants this spring and love those so I bought some early since they're hard to find. I'll have to get up the courage to go back and investigate in a bit...

Looks like everything there is pulling through okay, thanks to your TLC (and your friend's warning)... the picture inside the tunnel is very fun!