5 Reasons to Plant in the Fall (not Spring)

It’s generally recommended that spring and fall are the best times to plant. Here’s why fall is the best time of year to add new plants to your desert garden.

There’s a gardening rule of thumb that spring and fall are the best times to plant, and that holds true in temperate four-season climates. But, like most gardening advice, it’s not meant for the desert southwest — things are different here!

Here are five compelling reasons fall is a better time than spring to add new landscape plants to your desert garden.

Spring is Hot, Dry, & Short

The spring planting season in the desert is short. Most experienced gardeners and the University of Arizona Cooperative Extension consider March 15 to be last frost date in Pima County.

And then before you know it, it’s hot, dry, and windy. It may leave you wondering, “What the heck happened to spring?” 🤔

If you’ve gardened elsewhere, it can be a shock to learn that…

• There are no “April showers”. It’s not unusual to go months without rain in spring.
• The first 100-degree day occurs in April or May.
• Hot, dry June is the most challenging month for plants.

Spring is unforgiving. It’s upsetting when you forget to water or put up your shade cloth just once, and now your new plant is toast. 😢

Fall, on the other hand, is easier on plants. Even if there is a hot spell, the days are getting shorter, the nights are getting cooler, and the sun is getting less intense.

Plants Have More Time to Get Established in the Fall

When planted in the fall, a plant has three full seasons — fall, winter, and spring — to grow new roots and get established before it has to contend with the blistering heat of summer.

Compare that to planting in spring when the time a plant has to acclimate is measured in weeks.

Because our winters are relatively warm and sunny, the soil stays warm and plants can continue to put out new roots all winter.

Taylor Lewis, the nursery manager of UC Davis Arboretum, explains it like this,

“When the air temperature is cooler than the soil temperature, plants put more energy into root growth without new top growth, which results in heartier root systems and stronger plants overall.“

There Are Fewer Insect Pests in Fall

Spring through summer is peak time for insect pests of all kinds. But during the fall the number of insects naturally declines.

By planting in the fall, you miss the peak activity of caterpillars, white flies, spider mites, ants, grasshoppers, aphids, leafcutter bees, and other bugs that enjoy making a meal of your plants.

Planting in the fall gives them three seasons to become resilient to the next cycle of insect damage.

When exactly is “fall”? In hot, dry places like Tucson and Phoenix,
the ideal window for planting is between the end of September and mid-November.

Fall Planting Reduces Transplant Shock

Being transplanted is stressful on a plant. That’s why it’s called “transplant shock.” Let’s take a look at the journey from the garden center to your home garden from a plant’s point of view.

It gets taken out of the garden center, a cushy place where it’s been watered generously, and the microclimate is humid. It’s probably been under a roof or shade cloth, protected from sun, wind, and temperature extremes. Before it arrived at the nursery center, it most likely was grown in an even cushier greenhouse.

Once it arrives at your home, it experiences a major change in its environment and the care it receives. And when it gets planted in the ground, it is now living in a different kind of soil with a different microbiome. And it probably incurred some root damage, no matter how careful you were.

Clearly, a new plant faces many challenges, but you can lessen its load and reduce transplant shock by planting in the fall.

Avoid putting new plants in a hot car.
Plants can die from getting broiled during their trip home.

Fall is Easier on People, Too

Planting in fall is not just easier on your plants, it’s easier on us gardeners, too.

Here’s what I like about fall planting:

• The days are getting cooler and shorter, the sun is less intense. It’s a joy to be outside again.
• I can shop for plants (my favorite thing!) and get them in the ground while the weather is delightful.
• I’m less concerned about my new plants, knowing that temperatures are moving down instead of up.
• There is less maintenance – less watering and providing shade, and fewer insect pests to contend with.

Exceptions to Fall Planting

As with any rule of thumb, there are exceptions.

Cactus can be planted anytime, but establish more quickly when planted in spring or early summer. However, you may need to protect them from the sun during the first summer.

The best time of year to plant citrus trees after the last frost date in spring. While they can be planted in the fall, newly planted trees are susceptible to frost damage and will need protection in the winter.

Palm like the heat and do best when planted in May.

Learn more about what you should and shouldn’t plant in spring in our article What to Plant in Spring (Month by Month).

Did you enjoy this article?
Sign up for our weekly newsletter
where you’ll find more great info on creating &
maintaining a beautiful, carefree desert landscape.