Dry farming watermelon, onions leeks and garlic - Ask Extension
Hello, can you provide any information on dry farming onions. Leeks, garlic and watermelon?
Thank you
Knowledgebase
Dry farming watermelon, onions leeks and garlic #893699
Asked March 05, 2025, 3:30 PM EST
Hello, can you provide any information on dry farming onions. Leeks, garlic and watermelon?
Thank you
Clackamas County Oregon
Expert Response
This is a great question to send to the Dry Farming Collaborative Mailing List. You can sign up here: https://lists.oregonstate.edu/mailman/listinfo/dry_farming_project
Here is information from OSU's Vegetable and Dry Farming Programs that may be helpful. I have some concerns about getting enough water to the garlic and onions once the spring rains stop. You'd likely be able to have green garlic without supplemental irrigation.
Fall planted onions and garlic can be grown with minimal watering.
Onion:
Here's onion information from the Oregon Vegetable Production Guide:
In overwintering onion production, use fall season water sparingly. Apply only enough water to establish a good stand, and enough growth so that onions will over-winter successfully. Onion plants should be about 1/4 inch in diameter as they go into the winter and go dormant. In spring, irrigate as necessary to maintain vigorous growth. Irrigation is generally terminated two weeks before harvest.
Garlic: https://horticulture.oregonstate.edu/oregon-vegetables/garlic-1
IRRIGATION
No irrigation is necessary in fall after planting if soil moisture was adequate at planting depth. If not, one irrigation may be needed to establish the planting.
In spring, keep garlic growing actively. From 6-10 inches of water may be necessary in western Oregon in late spring and summer. Approximate summer irrigation needs for the Hermiston area have been found to be: 3.5 inches in May, 5.0 in June, 7.5 in July, and 7.0 in August. Water stress during clove development has been implicated in witches-brooming.
Continue irrigation until cloves are well filled and bulbs are the desired size. Examine bulbs regularly as harvest date approaches for presence and condition of the scales surrounding the bulb. Terminate irrigation when there are 2-3 matured scales surrounding the bulb. If irrigated too long, these scales will deteriorate one at a time until there are none, causing bulbs to shatter at harvest. Garlic should not be irrigated once the tops begin to fall and become dry. In the Willamette Valley, irrigation is usually discontinued around mid to late June for California Early garlic and around July 4 for California Late Garlic.
Mid-May to mid-June is a critical period for Botrytis gray mold. Exercise care in disease control and irrigation.
Soil type does not affect the amount of total water needed, but does dictate frequency of water application. Lighter soils need more frequent water applications, but less water applied per application.
Melon trials (including watermelon) from 2019 Dry Farmed trials in Corvallis: https://smallfarms.oregonstate.edu/sites/agscid7/files/melon_variety_handout.pdf
Here is information from OSU's Vegetable and Dry Farming Programs that may be helpful. I have some concerns about getting enough water to the garlic and onions once the spring rains stop. You'd likely be able to have green garlic without supplemental irrigation.
Fall planted onions and garlic can be grown with minimal watering.
Onion:
Here's onion information from the Oregon Vegetable Production Guide:
In overwintering onion production, use fall season water sparingly. Apply only enough water to establish a good stand, and enough growth so that onions will over-winter successfully. Onion plants should be about 1/4 inch in diameter as they go into the winter and go dormant. In spring, irrigate as necessary to maintain vigorous growth. Irrigation is generally terminated two weeks before harvest.
Garlic: https://horticulture.oregonstate.edu/oregon-vegetables/garlic-1
IRRIGATION
No irrigation is necessary in fall after planting if soil moisture was adequate at planting depth. If not, one irrigation may be needed to establish the planting.
In spring, keep garlic growing actively. From 6-10 inches of water may be necessary in western Oregon in late spring and summer. Approximate summer irrigation needs for the Hermiston area have been found to be: 3.5 inches in May, 5.0 in June, 7.5 in July, and 7.0 in August. Water stress during clove development has been implicated in witches-brooming.
Continue irrigation until cloves are well filled and bulbs are the desired size. Examine bulbs regularly as harvest date approaches for presence and condition of the scales surrounding the bulb. Terminate irrigation when there are 2-3 matured scales surrounding the bulb. If irrigated too long, these scales will deteriorate one at a time until there are none, causing bulbs to shatter at harvest. Garlic should not be irrigated once the tops begin to fall and become dry. In the Willamette Valley, irrigation is usually discontinued around mid to late June for California Early garlic and around July 4 for California Late Garlic.
Mid-May to mid-June is a critical period for Botrytis gray mold. Exercise care in disease control and irrigation.
Soil type does not affect the amount of total water needed, but does dictate frequency of water application. Lighter soils need more frequent water applications, but less water applied per application.
Melon trials (including watermelon) from 2019 Dry Farmed trials in Corvallis: https://smallfarms.oregonstate.edu/sites/agscid7/files/melon_variety_handout.pdf
