Friday, April 11, 2008

Soil Thermometers?

Has anyone actually used a soil thermometer?

Because of my situation, I'll be planting some things relatively 'late' that want a cold start, like peas (I remember my parents always planting them - even if there was some light snow on the ground - on or around St. Patrick's day). My copy of The Massachusetts Gardener's Companion discusses using a soil thermometer because seeds of different plants like to germinate at one temperature range, but grow at a completely different one. Has anyone actually used one, and found this to be true, and warranting use of a soil thermometer? Can I get away with just using a regular thermometer (i.e., like one that you might hang outside for air temp.?) or would that give me a false reading for some reason?

Any thoughts or suggestions would be appreciated.


kathy said...

Last year I used an aquarium/pond thermometer in my soil. I buried it a few inches down, left it an hour then checked it. I would think a regular thermometer would work fine. (The pond one has a protective plastic shield on it.)

Once you check one year, you'll get a sense of dates when your garden soil is a certain temperature range, and probably won;t need to use it the next year. It was helpful for me, because my garden is so shaded that it warms up slowly.

Margo said...

Fabulous!! Thanks for the feedback, that'll be so helpful. I got my first plot laid in this morning before the rain started. *whew* one down, so many more to go...

henbogle said...

I have one, you can see a photo on a recent post. I use it every spring, and find it especially helpfult as 1) I'm impatient, 2) my raised beds behave very differently from the regular garden. I suspect the difference between a soil and wall thermometer is the soil thermometer has a protective metal shield. Without that, you'll just need to be careful not to break the thermometer hitting a rock.

Ali in Maine

Forty_Two said...

What do you do if the soil is too hot...drink plenty of fluids and call me in the morning?

Old doctor joke.

Margo said...

Hi Ali,
Thanks for the feedback. I now feel more confident about using my thermometer - I'll just have to be gentle with it. I do want to be able to cold-start a few things (successfully) next year so I'm trying to be "good" about investing the record-keeping time & effort now.

forty_two: actually, if the soil's too cold for your seeds to germinate, you want to hold off on planting. If it gets too warm (later in the season) you want to wait until it cools down. Some seeds want to germinate at a warmer temperature and grow at a cooler range; others want a cool start and warmer soil for plant and fruit growth. Since there's some question of how cold the community garden meadows get (some parts are low-lying), I'll want to know some possible reasons why certain things I planted succeeded - or didn't - for next year's garden planning.
Science is marvelous, innit? :)

henbogle said...

Wow, great progress on the raised bed! That was a LOT of work.
Ali in Maine

Margo said...

Thanks Ali! I guess you must have seen my flickr pictures. 2 beds down, several more to go (assuming I can find enough wood!) I am WAY overdue for a blog post, and have 3 in draft... but yes, a lot of work. But I think it will be worth it: word around the gardens is that we have resident woodchucks, so an investment in guarding the garden seems worthwhile - through fencing, raised beds, and coldframe arrangements. *Whew*
Have been admiring your efforts as well! Looking forward to checking out the recipe blog, haven't had a chance to stop by yet. ttys :)

Emily said...

In a pinch, I use my meat thermometer. It's built to be poked into stuff.