Sweet Corn. Tomatoes.  Watermelon.  These are items that many Americans associate with the Fourth of July holiday.  Yet in most parts of the U.S., it is simply impossible to harvest a crop of any of them by July 4th.  Even with climate change.
Like most Americans, the favorite fruits and vegetables of Independence Day have immigrant ancestors.  Sweet Corn and Tomatoes are better known as Elote and Jitomate in their native Mexico.  And Watermelons were first cultivated in North Africa.
With their sub-tropical ancestry, all three of these crops are frost-sensitive, meaning that freezing temperatures kill them.   Yet in order to harvest them in late June or early July, they must be planted in early April.  In 2/3 of the continental United States, freezing weather is still a virtual certainty at that time.  In a dozen U.S. states, frost is still common in June!
Even in California, there’s no guarantee of harvesting these holiday favorites in time for July 4th.  Sweet corn has a narrow harvest window, meaning that when it is ready, it must be picked within a day or two.  And each plant only makes one or two ears.  It can’t be planted in the rain, and the seeds will rot if it rains too much after it is sown.  If you miss the planting period — 70-80 days prior to July 4th — or the seeds you plant rot, you have missed your chance to harvest in time for the holiday.  There is no such thing as “playing catch up”.  And there’s no “early bird special”, since corn harvested a week too early won’t keep.
Tomatoes and watermelon don’t have a “drop dead date” like corn.  They have a longer harvest period, which provides some leeway for planting early to ensure ripe fruit in early July.  But that means planting in March, which is generally both colder and wetter than April, increasing risk of frost damage or disease.  This can delay harvest or lead to complete crop failure, defeating the purpose entirely.  Many growers simply won’t take that risk.
Here at Terra Firma, we have microclimates that allow us to harvest all three crops in time for Fourth of July most years.  And some years, like this one, they arrive even earlier.  Over the years, we have developed a toolshed of growing practices that allow us to plant both tomatoes and watermelons in less than ideal conditions and protect them from freezing.  Sweet corn is more challenging.
From a weather perspective, this year was a cakewalk.  Both March and April were mild and dry — too dry.  We had to irrigate all the fields both before and after planting, literally unheard of here.  Our other big concern — frost — did not occur even a single time after planting.
We take a lot of pride in having sweet corn, tomatoes and watermelons in your CSA box this week.  We hope they help you enjoy the holiday despite the challenging times we are living through.
Happy Fourth!