Strawberries 101

Most of California’s strawberry production (about 60%) occurs in the Salinas/Watsonville area and the Santa Maria Valley- the place Darensberries calls home. About 40% of total fruit production comes from Ventura County and the south coast regions.  The San Joaquin Valley only makes up 1% of total California production.

What is surprising to most people is that strawberry growers plant transplants rather than seeds. The transplants come from either the low-elevation nurseries of the Sacramento and San Joaquin Valleys or the high-elevation nurseries in Northern California.

Different growing regions plant at different times. Plants kept in cold storage for a period of time after being harvested form the nurseries are called “frigo plants”. These plants are planted in the Central Valley in the summer so they will bear fruit in the spring. Frigo plants are also planted in Ventura County and the Santa Maria Valley in the spring or summer. These plants will be ready to harvest in the fall. Both of these planting dates are considered summer plantings. Most of the strawberries in California are planted from fresh-dug transplants in the fall (September to mid-November). These plants will be harvested the following year peaking in May. This planting schedule is called a “winter” or “fall” planting. Click here for more info.

All of the strawberry plants you see in the field are transplanted plants from a nursery. Nurseries propagate varieties of strawberry plants that are genetically identical. Here’s how it works: A plant is selected for its genetic traits by the breeder, in many cases, the breeder is the University of California. Strawberry plants send out shoots called “runners”, runners then develop roots and leaves and if left un-cut from the “mother” plant, the “daughter” plant will become completely self-sustaining in just 2-3 weeks creating another plant that is technically a clone of the mother plant. Nurseries use this ability to make millions of identical plants.

There are 2 types of nurseries: High-elevation and low-elevation. Low-elevation nurseries harvest their plants in December and January and are either transplanted in both high-elevation and low-elevation nurseries for the following year or put into cold storage for summer plantings in the fruit production fields. The high-elevation nurseries are harvested in September and November and planted immediately in fruit production fields.

When you’re eating a strawberry, you’re eating what used to be a cute little white flower. It takes 25- 60 days for a flower to become a mature strawberry. Here’s how it happens:

Flower Diagram

 A strawberry flower has both male and female parts.  The Pistil is the female receptive part of the flower that is sitting on the Receptacle and the Stamen is the male pollen generating part. The pollen enters the Receptacle through the Pistils by way of wind, gravity or insects such as bees. Bees are not essential to strawberry flower pollination, don’t worry. Once the receptacle is fertilized, it develops  Achenes or seeds. These Achenes produce hormones that stimulate the development of the strawberry.  If all of the Achenes are properly fertilized, a perfect strawberry will develop, however, strong wind, insects, extreme heat or cold can prevent perfect fertilization and this is what causes green tips and misshapen fruit

The typical strawberry field in California is replanted every year. There are growers who keep their plants for 2 years. These are called second year plants. However, second year plants have more pest problems and the quality and over all yield decreases in the second year.  

There are two planting schedules: Fall plantings and summer plantings.

Fall plantings yield earlier fruit  and have an over-all seasonal yield with better quality fruit. About 90% of strawberries in California are planted in the fall. These plants will general start bearing fruit in the early spring.

Summer plantings are done primarily in Central California and yield fruit a few weeks later than fall plantings. The advantages to summer planting are hardier plants and an increased vigor.

A Newly Planted Field

     A Newly Planted Field

young field 2

And Now, We Wait

young plant

A Young Plant

Plants have the amazing ability to know what time of year it is without a calendar. They do this by reacting to photoperiod, or length of the day. Strawberries use the day length to determine when they should produce flowers, push out more leaves or send out runners (see nurseries). Two types of strawberries have been bred, Short-day varieties and day-neutral varieties, and they both react differently to day length.

Short-day varieties shoot out flowers when the day length is 14 hours or less. Temperature does have an effect on flower production though. If the temperature is higher than 60°F, the plant will require less than 14 hours to start flowering. Short-Day varieties are planted in the Ventura and Santa Maria growing regions because of their early fruit.

Day-neutral varieties will produce flowers regardless of the day length as long as the temperature is reasonable.  Sometimes temperature can affect flowering in day-neutrals however. Temperatures less than 45°F will keep the plant from flowering. Day-neutral varieties are most often planted in the Watsonville/Salinas area to capture the later markets in summer and fall when the short day varieties are slowing down in production.

Growing Areas