Jang growers notes · Updated October 2026

How to grow radishes with the Jang seeder

Ready in about three weeks and sold by the bunch. One of the quickest returns on a bed. Settings, timing, yields and step-by-step notes for the JP1 or JP5.

Download the growers notes (PDF)Shop Jang seeders

Quick answer

Jang settings for radishes

Set the Jang to the F24 roller with 14 x 10 sprockets (front x rear) and the brush down, and seed 10 rows on a 30″ bed.

Roller	F24
Sprockets (front x rear)	14 x 10
Brush	Down
Rows per 30″ bed	10
In-row spacing	1″
Seed per 100′ bed	130 g (+/-)
Cultivars	French Breakfast, Easter Egg, Rover
Days to maturity	22 days
Harvest window	14 days
Harvest size	1.5-2″
Yield per 100′ bed	200 bunches (14-16 per bunch)

Bed figures are for a 100′ x 30″ bed. From the Paperpot Co. Growers Notes, developed with farmers Erich Schultz (Steadfast Farm) and Seth Davis. Adjust for your climate and conditions.

Bed preparation

Broadfork the bed to aerate and loosen the soil.
Smooth and shape the bed with a bed prep rake, removing any debris.
If the previous crop was fertilized, radishes will do fine without reapplying. If not, either layer on 1″ of compost (enough to mostly cover the native soil) or sprinkle on alfalfa meal and/or pelleted chicken manure.
If you layer compost, don’t tilth it in, so surface weed seed stays smothered. If you add amendments, tilth the top 1″ to mix them in.
Irrigate for 10 to 14 days* to germinate weed seed in the top layer of soil, then flame weed once the weed cotyledons are up.

Seeding

Set up the Jang: F24 roller, 14 x 10 sprockets (front x rear), brush down.
JP1: seed 10 evenly spaced rows across the bed.
JP5: fill all five hoppers and seed the bed in two passes, one from each side.

Bed layout

Irrigation

Water with overhead irrigation or four lines of drip. The first watering chases off flea beetles already in the soil.
Right after that first watering, cover the bed with floating row cover (insect netting in warm weather) and weigh the edges down with sandbags every 5 feet. It only comes off for cultivation and harvest, so flea beetles never get a chance at the leaves.
Water right over the cover.
Keep watering through hot days in the warm season.

Cultivation

14 days after seeding, cultivate with a flex tine weeder (2 passes per bed).
After that, the canopy shades out new weeds.
Put the row cover back right after cultivating.

Harvest

Pull radishes with their tops on and bunch them in the field, 14-16 per bunch at 1.5-2″ each.
Pile bunches in the path and collect them in a tote at the end of the bed.

Washing and packing

Spray each bunch with a washdown gun over a root wash table, turning it until all the soil is off.
Store radishes at 35°F in a plastic bag or tote to keep them moist and crisp until market.

*All timing varies with your climate, soil and season.

Suggested tools

Job	Tool
Seeding	Jang JP1 or JP5
Aeration	Broadfork
Tilthing	Tilther, power harrow or precision depth roller
Bed shaping	Bed prep rake
Weed control	Flame weeder
Cultivation	Flex tine weeder

Questions

Radishes with the Jang: FAQ

What Jang roller do I use for radishes?

F24, with the 14-tooth sprocket in front and the 10-tooth in the rear, brush down. That gives about 1″ between seeds. Test the roller at the bench with your seed lot before you go to the bed.

How much seed do I need?

About 130 g for a 100′ x 30″ bed at 10 rows. Round up when you order.

How long until harvest?

About 22 days from seeding, with a harvest window of about 14 days. Timing varies with your climate, soil and season.

Where can I get a Jang seeder?

Jang JP1 and JP5 seeders, rollers and parts are at Modern Grower. Questions? Email hello@moderngrower.co.

More growers notes

Other crops

arugula · baby kale · baby lettuce · baby spicy greens · baby brassica greens · spinach · carrots · salad turnips · snap peas. All settings in one place: the Jang seeding chart and the growers notes hub.