University of Minnesota horticulturists Annie Klodd and Natalie Hoidal responded quickly to stories from farmers around the state who have been discouraged by flooding, late frosts and hail this spring.
The pair collaborated to present about options growers still have to replant for marketable produce this season. The webinar also covered options to create more sustainable fruit and vegetable production for future years, in the event the weather continues to be fickle.
Northern Minnesota gardeners are well aware that the region has a short growing season. This year there was a mid-April snowfall of several inches and a mid-June hard freeze in many areas. Rather than throw in the towel, Klodd and Hoidal encouraged growers to remain flexible. Some possible strategies are listed in the sidebar box.
Growers were also encouraged to consider longer-term strategies to adapt to wetter, cooler spring weather.
Increasing reliance on perennial food crops was one way Klodd and Hoidal recommended that growers increase their early offerings without having to enter fields that are too wet in the spring. Beyond the ubiquitous rhubarb, they suggested asparagus and perennial onions have a lot of potential for this region.
Short-season crops like lettuce, spinach, kale, radishes and spring onions can be replanted every one or two weeks for a season-long harvest, especially if there is partial shade to prevent overheating and bolting. Bolt-resistant varieties are available from many of the bigger seed houses.
Inter-cropping, fast-maturing crops like lettuce are among those that take longer to mature and can redeem the space as well as provide a little shade for delicate varieties such as lettuce.
“Extending the harvest is a succession-planting goal, but a similar outcome can be achieved by planting two varieties of the same vegetable that have different days to maturation,” said the presenters. They cautioned that maturation dates and other varietal attributes may not hold true for northern Minnesota if they were trialed in a radically different growing zone.
July and early August are prime times for planting bush beans, cabbages, carrots, daikon, beets and turnips for fall harvest, especially if the more heat-sensitive vegetables get some protection from shade cloth and frequent watering.
Klodd and Hoidal encouraged growers to step outside their comfort zones and try some vegetables or varieties they have never grown.
“Just because a variety is your favorite, don’t get paralyzed by that. New, short season and disease resistant varieties are being developed all the time. Try them out,” said Klodd.
The presenters also urged growers to consider crop insurance if appropriate to their situations.
The videotaped presentation is available on YouTube.
Late planting, replanting and succession planting strategies for northern Minnesota
• Plant more than one variety, with different days to maturity.
• Replant every 7-12 days throughout the season to ensure a continuous harvest. Stop planting by counting backwards from the first expected frost date.
• Take advantage of harvest scheduling spreadsheets to schedule your planting, transplanting and harvest dates.
• Keep good records to become an expert in your own growing area.
• Plant extra seedlings of warm season crops like tomatoes and peppers, in case you need to replant. Extras can be sold at the local farmers’ market.
• Plant fall crops like carrots, daikon, kale, turnips , kohlrabi in July and early August.
• Make use of row covers, shade cloth and other season-extending strategies like high and low tunnels.
• Try new varieties that are bred for disease resistance, resistance to bolting, and growing under plastic.