Dear Tom –
How to you plan the timing of succession crops? Thanks
– Adam in Fairview
We sow nearly every week starting in February and ending in late September. Some crops like peppers are sown once for the season but we sow many crops repeatedly through the season to meet market demand. The timing of those successions is complicated. Here are some of the factors that influence when we sow succession crops.
Last Year’s Sales Records
The best way to tune up our succession planting schedule is to look at our sales last year. If we show that we brought home a succession crop (salad mix for example) in late May then we try to sow a little less earlier in the year or skip a sowing to keep production lower in late May, If we sold out cucumbers consistently, then we sow more or sow more often next year to try to meet demand.
We added an important column to our sales records a few years ago. To our “took to market” and “brought home from market” columns on the sales spreadsheet, we added a column for the amount we “wish we had taken to market.” For example, if the market runs until noon and cucumbers are gone at 9:00 we need to sow more or more often next year. If we had one case and needed four, then we should sow four times as much next year.
Early in our farming careers we sowed lettuce every week starting in mid February and ending in late summer. With that approach we had a lettuce glut in May and a shortage in fall. One way to look at the cause of these problems is to think of the “momentum” of the warm summer days that carries over into fall but the days are growing shorter – it’s still warm but the days are shorter so the plants grow less each day. In spring the early plantings have short days and cool temperatures so later plantings catch up with earlier ones – plants sown weeks apart are harvested a few days apart – producing a glut instead of a steady supply.
I could not figure out the math of this relationship so one year we kept careful time to maturity records for lettuce. To harvest the same amount of lettuce each week we sow every other week from February through mid-May, every week from mid-May through mid-July and twice a week through mid-August.
Seasonal Customer Demand
But steady lettuce supply may not be what you need unless you are selling only to grocery stores or CSA customers. The customers at one of our markets have home gardens so they don’t want lettuce in the spring. On the other hand they only plant lettuce once and need lettuce in July and August. Restaurant customers want lots of lettuce in tourist season with a peak during “leaf looker” season. Everyone wants slicer tomatoes for the Fourth of July but their home garden tomatoes start bearing in August. Hanging baskets are big on Mothers Day but hard to sell in August. School and soccer season starts in the fall and tailgate demand sometimes drops off. In contrast, tailgate demand once grew slowly in the spring but now it seems that we have more customers than produce on opening day.
Disease Cycles and Crop Preferences
Another factor affecting succession planting is how happy the crop is in a particular season (as well as how happy its diseases are). For example, we can pick a planting of summer squash for several weeks in June but mildew usually shortens the picking period later in the season. In theory we should plant more to account for that effect. Some growers switch to “summer” lettuces because they bolt more slowly but we have found that everything about those varieties is slow – they just grow slower. Slow growing lettuce is a problem with our cool damp mornings. We now just stay with the spring/fall varieties now and watch them more carefully for signs that they are considering bolting.
Back to Sales Records
Since no two seasons are alike and the factors mentioned above add up to a very complicated set of relationships, my best suggestion is to look at your “what I wish I had” column for the past several years as you decide how to plant succession crops this year.
Best wishes for a steady harvest.
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Tom Elmore is co-owner and operator of Thatchmore Farm in Leicester NC. He has grown certified organic fruits and vegetables for 25 years and serves on the Boards of the NC Greenhouse Vegetable Growers Association and the Organic Growers School.