May 23, 2000
Heating Up Your Tomatoes   

          Wow, Memorial Day seemed to sneak  up on me this year.  I’m sure this has a lot to do with the cool, rainy April we had.  Even May, so far, has been on the cool side.  Last week we had to endure a “frost advisory” and I heard that “south Charlton” (wherever that is) went as low as 29 degrees.  I noticed a lot of cloth-covered plants on the morning of 5/16.  I assume that these were annuals that were planted with great exuberance during the warmer days the week before.  I think that the happy go lucky April weather of ’98 & ’99 caused a lot of folks to forget what “normal” spring weather is.  Well, the slightly “sub-normal” temperatures this year have reminded us all.  Memorial Day has always been an important day on my gardening calendar.  Depending on the forecast,  I consider the week before and after Memorial Day planting time for all the tender annual flowers and vegetables.  If you go by the book, it isn’t until now that we can consider ourselves to be beyond the threat of frost.  This is, of course, is based on an average of last frost dates so, there’s still no guarantee that there won’t be another frost after Memorial Day.  It has happened.  Having said that I want you to know that I’ll be proceeding with my planting of flowering annuals even before you’re reading this.  As far as the vegetable garden goes, I’ll start planting as soon as the soil dries enough to till which, hopefully, will also have already occurred by the time you’re reading this.

                While we’re all anxious to plant, it’s important to remember that the most popuplar vegetables grown are descendents of varieties that were discovered (or plundered, depending on your view of 16^th century Spanish colonialism) in Central America.  Tomatoes, squash, peppers, beans, corn and many others were staple crops in the empire of the Aztecs.  While Cortez and his conquistadors had no appreciation of Aztec culture, they, along with their Jesuit partners, were “religious” about sending anything of value back to the king and queen at home.  While the wealth of gold has long been spent, the horticultural treasure continues to feed and delight us.  The diet of Europe before the “discovery” of the New World must have been very bland indeed.  The hallmark of Italian cooking is tomato sauce yet; they didn’t cultivate tomatoes in Italy until after 1600!  We associate potatoes with the Irish but there were no potatoes in Ireland until they were brought back from the New World.  There WAS wheat in Europe so, as far as I can figure, they were real “meat & bread” folks until the ships returned from this side of the Atlantic.

                The point of all this is that many of our vegetable crops, with their Central American roots need lots of heat to perform well in our northern climate.  There are many tricks gardeners use and I’ll share a couple of them.

                To get our tomatoes to mature and start producing sooner, we need to increase the air and soil temperatures around our transplants.  You can use hotcaps that you’ll buy at the garden center or make your own from plastic water or milk jugs.  To make a hotcap from a plastic jug just take a sharp knife and slice an X through the bottom of the jug.  The center of the X should be in the center of the bottom of the jug.  This will give you four flaps that you’ll bend outward so you can anchor the jug to the ground with rocks or long nails to keep it from blowing away.  Be sure to remove the cap of the jug to allow excess heat to escape.  We want to warm our transplants, not cook them.

                You can also cover the soil at the base of your tomatoes with a sheet of black plastic.  The black plastic will warm up in the sun and trap that heat, warming the soil below.  Tomatoes love warm soil. 

                If you use tomato cages for support, you can install them as soon as you’ve planted your tomato seedlings and wrap the cage with clear plastic.  The clear plastic wrapped around the tomato cage creates a little greenhouse that’ll bring the temperature up to levels that tomatoes prefer.  Leave the top of the plastic-covered tomato cage open to let excess heat escape.  On nights that you expect temperatures to fall below 50 degrees, cover the tops of your “mini-greenhouses” to keep the temperature up overnight.  Don’t forget to uncover them in the morning or they’ll cook. 

                When I’m running late with my planting, there’s another trick I’ll use to get seeds (like beans) to sprout in the shortest possible time.  I’ll sow them in a shallow trench with soil built up on either side of the trench.  Then I’ll cover the trench with my “germinating fabric” (also known as remay).   I can anchor the fabric with stones or tuck it into the soil to keep it from blowing off.  The fabric will allow light and water to pass through but will trap enough heat to warm the soil, getting my seeds sprouted without cool weather delay.  As soon as the seeds sprout, I’ll remove the fabric at let them enjoy the sunshine.

                I hope the weather cooperates and we’ll all be able to finally dig in and get the crops in.  I hope I don’t hear that dreaded “F” word until October.  Thanks for the read.