UP Sprout

Warm Season Crops



IMG_3537


Spring is Here!

The days are warming up and growing longer… you might even notice powdery mildew on your winter kale or see your lettuce bolt and turn bitter overnight. It’s time to transition your garden from cool season plants to warm season crops!


Warm Season Crops: When, Where, and Why.

San Diego County contains two USDA Growing Zones: 10 and 9. These areas have differing average annual minimum temperatures during the winter.

Growing Zone 10a (higher average temperature):  Coastal San Diego, from La Jolla to Imperial Beach

Zone 9 (lower average temperature):  Desert regions west of el Cajon and Santee

The majority of San Diego is Zone 10a. Growing zones matter because they give suggestions on the ideal planting time. For example, Zones 9 and 10 have two basic seasons (hot and cool), but Zone 5 in Nebraska has a single growing season of April to October.

Your location within San Diego will determine the best time for you to start your new plants. For example, if you live in the warmer Zone 10, you can plant the warm season crops earlier. San Diegans living in easterly Zone 9 should wait for the warmer days of April to plant their tomatoes, etc. Find out the zone you’re in by entering your zip code at the USDA website.


8.16 Corn


Setting the Stage:

You can plant the warm season crops listed below at any time during the suggested months, but consider starting them early to take advantage of the long growing season! Here are some tips to follow while you prepare your garden:

  1. Refresh your garden bed: pull the spent plants (and if possible, compost them!) and fertilize the bed with organic vegetable fertilizer. Avoid fertilizer with a high nitrogen count (anything with double digits) because this creates an unnatural amount of quick, weak growth.
  2. Try not to step on the bed, and avoid massive soil turnover in order to maintain the health of the soil ecology that’s built up in the cool months.
  3. If you want to seed tomatoes early, it’s recommended that you do so indoors with heat lamps because they require 50-90 warm days (depending on the variety) to reach maturity. However, for a head-start and less headache, we recommend buying seedling starts instead.
  4. Adjust irrigation settings to accommodate for longer daylight and warmer weather.

Growing food in Southern California’s warm season is incredibly rewarding. Harvests are often heavy and varied, and you can bite right into the fruits of your labor!


Eggplant and Okra


What To Plant Now:


Beans: March-August

Corn: March – July

Eggplant: April – June

Melons: April – June

Okra: April – June

Peppers: April – June

Squash, summer: March – August

Squash, winter: April – June

Sweet Potatoes: April – June

Tomatoes: March – July

Potatoes: August – Sept