Plant During Winter but Not As Good As Fall Planting

Q. I would like to plant a pomegranate tree this Fall but I am worried that the weather is going to be cooling down soon. Do you think I missed my opportunity for planting, and should I wait for Spring?

A. Just because it is getting colder doesn’t mean you can’t plant. Ideally you want a few weeks of root growth in the Fall after planting. The timing may not be optimum for root growth when soil temperatures are cold, but it will still work out. If you find a variety you like, get it in the ground.

            Temperate plant roots (like pomegranate) grow best when soil temperatures are between 60 to 75F but they still grow even when soil temperatures are as low as 45F. They just don’t grow as fast. Try to plant early enough so that there are 4 to 5 weeks of warm soil temperatures before the soil gets cold.

Estimating soil temperature

            How to estimate the soil temperature? The best way is to buy a soil thermometer for about $15 and measure for yourself but otherwise you can make a rough approximation.  

Soil thermometer on Amazon

Soils are always a bit warmer than air temperatures. Take the average air temperature over the past couple of weeks (low + high and divide by two) and add 5 degrees. Surface mulch, rock or woodchips, conserve soil warmth in the Fall and insulate soil from heat in the Spring and Summer months.

            In my experience, using your sense of touch is accurate to within about 5 degrees F of temperatures ranging from the refrigerator (40F) to the spa (105F).

            Fall planting is always superior to Spring planting of winter hardy plants.