Now is the Time to Plants the Seeds for a New Alfalfa Crop

As alfalfa growers wrap up the long spring-to-summer season, some are already looking to plant the seeds for a new field of hay.

Yes, now through early October is the ideal time for growers to establish a new stand of the perennial crop in California, especially in the San Joaquin Valley, says Dan Putman, an alfalfa extension specialist with the University of California Cooperative Extension in Davis.

Now is the ideal time to plant new alfalfa fields in the Valley.

“I’ve seen so many failures with alfalfa from not planting at the right time,” Dan told a group of farmers at a recent alfalfa field day. Those who plant in late November, for example, often run into cold, wet weather, which isn’t conducive to good growth.

“It’s a slow growing seedling. We’re so eager to start harvesting the crop that we don’t realize we have to set it,” he said. During the first six months, it’s important for new alfalfa plants to establish deep roots – usually five to six feet deep.

Alfalfa seedlings need time to establish their roots.

By developing this deep root system, alfalfa can better withstand pest, weed and drought pressures. During the cold weather, winter weeds will compete with the young alfalfa.

A UC Agriculture and Natural Resources “Alfalfa Stand Establishment” manual published in December 2007 calls seedling establishment “a critical phase in the life of an alfalfa stand, impacting production for many years.”

Dan reports growers losing 1 to 1 ½ tons of yield because they plant their field a couple weeks late. A 1977-1978 field study in Yolo County and the Sacramento Valley found yields confirms the difference:

•     September 14 plantings yielded 17.2 tons per acre during the first two years
•     October 17 plantings yielded 16 tons per acre during the first two years
•    November 16 plantings yielded 14.5 tons per acre during the first two years

Dan also advises growers to work with their pest control advisors to determine the best varieties to resist pest and plant disease pressures in their area.In looking back at severe drought this season – which put a crimp on acreage – Dan describes alfalfa as the best crop to have in a drought, especially with its deep root systems. 

Proper timing of alfalfa planting can boost future yields.

Alfalfa originated in regions that endured long, hot dry summers and wet winters – like the Northern San Joaquin Valley. “You can roll with the punches in a drought year. It is a resilient crop. It will come back another day to yield well.”

Meanwhile, Dan mentioned some growers are testing buried drip systems in more than a dozen fields. Interest is widening as some growers report an increase of 2 to 2 ½ tons in yield. Drip provides more consistent watering throughout the season.

On the down side, drip systems are prone to rodent and gopher damage. “It is a challenge. They will chew on lines. There will be leaks.” Some growers have walked awayfrom drip because of the gopher problems. To be successful, growers must be willing ramp up their pest management game.