Before selecting crops for the upcoming season, review records for last season. Did you have any persistent disease issues in a particular crop? Did one crop do exceptionally well or very poorly? Did some varieties of lettuce bolt a lot earlier than others, leaving you without enough volume? By assessing where you’ve been, it’s easier to plan for where you want to go. – Crop Selection
The “Texas Vegetable Growers’ Handbook“, offered by Texas A&M AgriLife Extension, is similar to guides available in most states and can assist growers in choosing the best crops and growing practices for their farms. The guide offers this explanation for why crop selection is important: “Although vegetables are widely adaptable, successful production in a given area will be influenced [by] limiting factors: water, hail, wind, temperature, light, nutrition and markets. Variable levels of limiting factors limit yields or reduce potential for profitability. Therefore, base crop selection on the availability of these factors within a given location and growing season.”
The first step is to test your soil. “Identify which crops you plan to grow, and the soil lab will give recommendations based on your soil and crop needs,” advised Katie Campbell-Nelson of the University of Massachusetts Extension and Stockbridge School of Agriculture. “Each crop has specific fertility needs.”
Penn State’s “2013 Commercial Vegetable Production Recommendations” urges growers to “Always base plant nutrition decisions on a current soil test. Fertilizer is expensive, and soil tests are relatively cheap and the only indicator of true nutrient needs.”
Matching crops to the existing limitations of your soils is a smart step. Soil texture, compaction, cation exchange capacity and organic matter content are just a few of the variables that can impact the crop. Planting crops that are well-suited to your soil characteristics gives you a better chance of success. Growers can have an impact on soil characteristics through cultivation practices, by adding amendments, using certain planting methods, or employing techniques to alter factors such as soil temperature, moisture retention or compaction. However, working with a soil that already meets most of a given crop’s needs increases the chances of success.
Mineral nutrition issues can be difficult to remedy and can have a major impact on certain crops. “For example, boron is toxic to beans, but prevents hollow heart in brassicas. So if a soil is high in boron, grow brassicas,” Campbell-Nelson said.
Different varieties of the same species can have different nutrient requirements. Select varieties that are suited to your soil’s fertility levels.
Guy Ames, an orchardist and horticulture specialist with the National Center for Appropriate Technology (NCAT), focuses on locally and regionally adapted fruit varieties. Using adapted varieties allows for increased disease resistance, and fewer inputs will be needed to reap a bountiful, healthy crop in an economically profitable manner.
“What should be growing in your area? It may not be what you expect, and it certainly won’t be what your customers expect,” Ames said. Common cultivars are not always the best choice. Those that have been bred for local production may not be widely known, but will be most adaptable to the environmental stresses present in any given locale.
Diseases arise due to the right combination of pathogen, host and environmental conditions. Choosing crops and varieties that are resistant to known disease issues, along with having a good crop rotation plan to break disease cycles, can help to minimize soilborne pathogens. “Selecting crops with disease resistance is really important,” Campbell-Nelson emphasized. Properly identifying diseases will not only help with disease control for the current crop, but also with ongoing crop planning. Services such as the University of Massachusetts diagnostic lab can assist growers with this step.
Likewise, some species of plants are more tolerant of certain insect activity than others. Planting crops or varieties that have insect resistance is important if a pest issue is already known to exist. Planting different varieties in succession can be possible, using the most insect-resistant varieties when pressure is the highest and switching to a variety with better flavor or storage characteristics once the pressure abates.
Daylight hours are another concern. Onions, for example, are influenced by day length and must be selected so that the plant’s needs match the actual growing conditions. Proper timing of seeding is important, as bulbs need an increase in day length to develop. Similarly, the timing of seed sowing for overwintering carrots is important. If they aren’t sown by November 1 in New England, you’ll end up with woody carrots instead of sweet ones, Campbell-Nelson said.
Crops that need significant light and warm temperatures for growth and optimal flavor, such as melons, require special attention. Where the growing season is short, choosing a melon variety that matures a week or so earlier than other varieties can make a difference in the crop’s success. Choosing crops with planting and sowing needs that make sense for your farm is important.
If a field is prone to wind damage, select wind-tolerant crops, or find a compatible field crop to serve as a windbreak. If your region experiences regular heavy rains in late spring, choosing a crop that is seeded after the rainy period can minimize headaches. If summer drought is an issue, a crop whose water needs are at their maximum during this time is going to require more irrigation and other inputs than crops with minimal water needs. The water needs of any individual crop vary depending on growth stage. Planning for this can minimize stress for both the plant and the grower.
Planting crops that are mutually beneficial is another method that can increase quality and yield while decreasing negative effects of insects and diseases. While beets and beans are compatible and do well together, beets and pole beans suppress one another’s growth and shouldn’t be planted in proximity to each other. Planting chives within, near or alongside carrots can improve the flavor of the carrots and increase their growth. Planting crops that can serve as a trap, diverting insects or wildlife from the cash crop, is another consideration.
If you have too many crops competing for attention at once, you may not get the jobs completed in a timely manner, which can impact quality and yield. Know when important production activities, such as staking, pruning and harvesting, are going to occur, and choose crops that complement the other work being done on the farm. This will streamline labor and increase efficiency, which will impact profitability.
Timing the application of pesticides or herbicides for one crop without negatively impacting another crop can be complicated. Is an application going to happen at the same time an adjacent crop needs to be harvested? Will drift present a safety issue? Will chemical applications harm pollinators active on a nearby crop? Selecting crops to avoid these issues can help.
If the sowing, transplanting, growing or harvesting of a crop is going to require additional equipment, is the investment feasible? Would you be better off planting a crop that utilizes the equipment and skills already being employed on the farm? Adding a crop that needs special handling can add to your time, labor and equipment expense.
Harvesting and postharvest needs can also impact crop selection. Who is doing the harvesting? When does it need to be done? How will it be accomplished? Whether mechanically harvested, handpicked by farm employees or customer-picked, labor practices and availability can make a difference in crop and variety selection. Postharvest needs may be a limiting factor, particularly if a crop requires refrigeration or other special treatment.
Peak market demands might not coincide with the optimal growing conditions for your farm. Having a given crop ready for harvest at a given time may mean additional inputs and expenses, such as using plastic mulches, raised beds or other means to warm the soil, utilizing transplants instead of direct seeding, or using row covers. Spring broccoli, for example, may need to be managed for insect problems, but the pressures may be less for a fall crop. Late sweet corn may need earworm control, while high-season corn isn’t at too much risk. Careful variety selection can help, with some varieties being more adaptable to conditions seen at specific times in the season.
Planting a crop to meet a market demand can mean altering conditions through cultivation practices, adding infrastructure such as irrigation or a hoophouse, or utilizing chemical inputs to control intense pest or disease concerns. Meeting the demands of the market might mean choosing particular traits, germination times or maturity dates. Desired traits may be different for wholesale distribution, farm markets, restaurants or other outlets. While ability to withstand packing and shipping is a must when selling to distributors, flavor and taste is going to win out for farm-to-table chefs, and easy-to-harvest, tasty varieties might be the best choice for pick-your-own locations. Pick-your-own turnips may not be a hit with customers, but a wholesale market might exist.
For winter markets in colder areas, planting crops that are less susceptible to freeze damage can extend the season. Kale, beets, Brussels sprouts, parsnips and rutabagas are able to withstand freezing and can still be harvested after cold weather arrives, making them good selections for season extension.
Campbell-Nelson advises growers to utilize the many resources available and be familiar with growing conditions on their farm. “Ask other growers or your local extension service about particular issues you may have,” she said. One recommended resource available to New England growers is the University of Vermont Extension’s Vegetable and Berry Newsletters, in which extension agent Vern Grubinger shares grower reports from around the area, including crop conditions, disease and pest issues, and market sales.
Many variables impact crop selection. Choosing the crops that best fit the existing conditions and cultivation techniques on your farm, and planning to manage or avoid known issues, can get your season off to a good start. By selecting the crops and varieties that best fit the inherent characteristics of your farm, you can maximize quality, yield and profit.