Garden, Plant, Cook!

Saturday, November 01, 2008

It is Going To Be 91 Today--First Frost Alert!

Dear Folks,

No I have not lost my marbles -- we are about to go into one of our seasonal adjustment 'zones' where the temps move suddenly (over about 14 days give or take) 15-20 degrees up or down. Since it is Fall - it will be down. By about November 10th, we will see overnight temp forecasts of 40 degrees. That is when you NEED to start paying attention to the possibility of 'soft frost' before dawn in many areas of the Valley of the Sun.

Traditional first frost in the valley is November 17th -- or there-abouts -- and will be colder sooner for every 1000 feet about the valley mean elevation of 1,000 feet above sea-level. That means folks at the 1700 and above elevation may see frost around November 7th, or there-abouts.

What is happening? As part of my on-going research into how best to garden successfully in the valley, I found by tracking temperatures at night (as well as during the day), that in our cool seasons, most residential areas have 'heat sinks' in the form of building walls, fences, poured patios, sheds and garages. What happens is these areas absorb heat during the day and release it at night -- all to the benefit (during cold times) of your plants. However, all that heat dissipates between about 4:30 a.m. and dawn, so that an evening temperature of around 40 at 11 p.m. the previous night can mean a 32 or less temperature by sunrise the next morning.

So I recommend folks cover frost sensitive plants with cloth, sheets, blankets, newspaper when the night temperature forecast is 40 or lower. No plastic -- it transmits the cold to the plants by contact.

Frost sensitive plants include young citrus trees, particularly limes and lemons, but also include those tender perennials you want to help winter over for next spring: tomatoes, peppers, eggplant and basil are some of the top much-loved edibles. They do not give you anything during the winter, and may look bedraggled, but their larger root system gives you a head-start on production when the soil starts warming up in March.

Enjoy the fall while you enjoy your garden!

-- Catherine, The Herb Lady