Call Me Inspector Gadget

I think I have mentioned before that both my wife and I like gadgets. When we combined our households a few years back, we found that together we often had 3 or 4 (or more) of every kitchen gadget ever invented. So it should be no surprise to anyone that I have a few gardening gadgets too. In fact, a couple of them are so handy that I thought they deserved special mention.

One of my most used gadgets outdoors is a PH meter. Soil PH is an important factor in successfully growing many plants. Simply put, if the PH is out of whack, the plants can’t take up the nutrients they need from the soil. Getting your soil tested by a lab is a great way to empirically measure the average nutrients and composition of the soil. And for many purposes that is all you really need to know. But when growing plants with very specific PH needs you might find a wide range of conditions in your own backyard.

soil PH meter

There are many acid-loving plants like azaleas, rhododendrons and blueberries that thrive in a very narrow range of low (more acid) soil PH, while others like lavender, lilacs, and many of the brassicas (cabbage and broccoli) prefer their soil more alkaline or near neutral. That’s why I decided to get a single-function PH meter. I use it to measure PH in a particular part of the garden. It keeps me from unnecessary applications of lime or sulfur to change soil PH, as well as letting me know when more adjustments are needed. When I first starting using it I was surprised by the variations I found.

Another gadget I use a lot is a thermometer. I have a soil thermometer made just for that task plus I also use a kitchen variety instant-read thermometer. Of course the instant-read one is also handy for baking and other kitchen applications.

soil and instant read thermometers

The soil thermometer is great for determining the proper time to plant many vegetables outdoors. Growing instructions from some sources are often vague, like “plant in cool soil” or “plant when soil has thoroughly warmed”. What do those terms mean? What is “cool soil” exactly? A thermometer takes away the guesswork. The one I got is weather proof so I can leave it outdoors in the soil.

It has the preferred temperatures for many vegetables printed right on the dial, but I use my reference books for determining the exact preferences. And just like PH, soil temps vary considerably depending on location. People are always asking me when it’s time to plant tomatoes. “Early May” is a good rule of thumb in these parts but the best answer is “when the soil is warm enough”.  I’ll plant my early varieties when the soil gets to 60F. I prepare the soil, stick the thermometer in, and wait. Plant them any sooner and they’ll just sit there and sulk. Plant them too soon and they’ll never get over it!

I use the instant read thermometer to take the soil temp when germinating seeds. There are so many variables to consider when starting seeds. My fluorescent light setup is in our unheated basement, and temps down there are quite chilly in winter, less so in summer. Of course the lights heat up the soil somewhat, and a heating mat heats it up even more. The seeds themselves don’t care about generalities – they want to know the exact soil temperature before they decide to germinate, and every species has their own preferences.

Readings I took today tell me the soil where my lettuce seedlings are growing is 72F, while the soil for the artichoke seeds is at 79F on the heating mat. The lettuce prefers it cooler (40-60F), and it no doubt is at night when the lights go off and the basement cools. I got well over 90% germination, so it liked the environment well enough. The artichoke likes to germinate in the 70-80F range, and since it started coming up in 8 days it seems happy too. When it comes time to start my tomatoes and peppers I might need more than a heating mat to warm the soil, but I have ways to do just that.

Until then, that’s enough blathering from Inspector Gadget. Now, does anybody need their temperature taken?