How Cold can Lemon Trees Get?

In this excerpt from my book Grow Lemons Where You Think You Can’t, I talk about how cold-hardy lemon trees are:

overwinter lemons.jpg

Lemons in Cold Climates

There are many options for overwintering lemon trees in cold climates because they tolerate more cold than many people realize.

MY LEMON TREES DID VERY WELL when I moved into a house with an old sunroom that stayed just above freezing in the depth of winter.

Sadly (for me), the dilapidated sunroom succumbed to a house renovation and my precious lemons were banished to an insulated garage for the winter. Normally, I kept an electric heater in the garage that I could flick on if the temperature plummeted.

But while we renovated, there was no power to the garage, and during a particularly cold spell, the temperature inside the garage dropped well below freezing.

I was heartbroken to think I’d lost my lemons.

Happily, they survived. Only a few branch tips died. For plants that I associated with Mediterranean climates,

I was delighted to learn that lemons are amazingly cold tolerant!

 

Many factors determine cold hardiness

Many factors determine lemon cold hardiness. It’s not an exact science.

Citrus expert Bob Duncan of  Fruit Trees and More  on Vancouver Island says to remember the temperature at which the fruit freezes.

Citrus expert Bob Duncan of Fruit Trees and More on Vancouver Island says to remember the temperature at which the fruit freezes.

For example:

  • Young plants are more tender.

  • Fruit and young shoots will be affected before older, woodier stems.

  • If the plant is already dormant from cool temperatures, it can better withstand cold than an actively growing plant.

  • With grafted lemon plants, some rootstock are more cold-tolerant than others.

 

The MOST Important Temperature to Remember

When I asked citrus guru Bob Duncan from the nursery Fruit Trees and More about lemon hardiness and minimum winter temperatures, he stopped me and took me back a step, saying: “With lemons the fruit is on the tree in the winter. The question to ask is ‘What temperature does the fruit freeze at?’” Bob went on to explain that the fruit of citrus is at risk at anything below -3°C (27°F).