2023-2024 Vegetable Growing Conference Tips 4

 

Alkindus lettuce from High Mowing Seeds

This is the last of my series on tips I learned at sustainable farming conferences the past winter. The sessions reported on here were at PASA.

Harvesting Techniques for Small and Medium Scale Farms

This was presented by Julie Henninger and Andy Russell of Goodkeeper Farm in Gardners, PA. They run a Full Diet CSA, with 7.5 acres of vegetables including five high tunnels and outdoor vegetables, and turkeys, cows and pigs. Their well-organized workshop covered their Top Crops (head lettuce, baby greens, carrots, bunched greens and roots); Pre-Harvest Prep (check list, harvest pouch, rubber bands, sharp knives, bins, other equipment); Techniques; Post-Harvest Work; Pitfalls to Avoid and Meet the Farmers.

For a harvesting pouch they use a nailbag that clips on the waistband, to carry their knives and rubber bands. For harvesting crops, they recommend the Hoss harvest bag. Both leave both hands free for picking.

Hoss Harvesting Satchel leaves hands free.

Goodkeeper Farm practices flaming or tarping to deal with weeds before they become a threat to their crops. All their lettuce is transplanted using a paperpot transplanter. This Japanese designed implement is imported to the US and is now also being made in the US. They favor the red butterhead Alkindus lettuce. See photo above.

For carrots, they grow 6 rows on a 30” bed, spaced as 3 pairs of rows with 2” between the pair. As they harvest the carrots by hand, they broadcast rye, to get the cover crop established as early as possible, and keep live roots in the ground for the most time. They have made a carrot washer from a cement mixer, reducing the size of the belt to slow the machine down. See Root Washers for Produce Farms.

Root Washers for Produce Farms, from University of Vermont Extension Ag Engineering

Top of their tips for techniques is to ensure each person masters the tasks first, limiting distractions. A strong role model demonstrates the technique and the expected pace. After getting those two aspects as second nature, the learner can start to have conversations and other distractions.

In the Pitfalls to Avoid, they list damaging the crops while harvesting, overloading harvest bins, using the wrong harvest gear, failing to invest in good appropriate equipment, dull cutting tools, and actions such as gathering different size bunches, that require re-bunching – try not to need to touch the crops again after harvesting!

Winter Market Gardening

by Catherine Sylvestre, the farm manager at Ferme de Quatre Temps, in Quebec, and co-author (with Jean-Martin Fortier) of the book Winter Market Gardener. Read my review here.

Cover of The Winter Market Gardener

Catherine gave both an introductory presentation and an advanced session with an excellent handout. At their zone 5b teaching farm, they have 27,000 sq ft of sheltered growing: 4 high tunnels, 3 greenhouses and one multi-bay shelter. They offer a two year program for students wanting to learn sustainable farming. They close for a two week break over the winter holidays, and plan their crops to be ready for harvest either side of that break. They need to sow in June for harvests before the break. They have five Principles of Winter Gardening:

  1. Use simple shelters, plastic-covered tunnels, for best profitability
  2. Add minimal heating. By adding 3 Celsius degrees (5.4 F degrees), they double their yields, and avoid using rowcover. Evening out the temperature between day and night reduces stress on the plants. Nutrients are more active if the soil is warmer.
  3. Increase the cold tolerance of the crops. This increases the sugars in the cells, making them more cold-tolerant from then on. Increase the airflow and expose plants to cold temperatures. They start this hardening off at the first frosts, and find that 7-10 days of chilling is needed to create a lasting result.
  4. Be aware that light is the limiting factor (especially for spinach). Their light in November is only one quarter of what they get in August. They plan to grow many crops to size in September and October. Although Asian greens can make some growth Nov-Feb, many crops will not. The ratio depends on your latitude, and is less extreme where we are in Virginia. Grow crops that are less affected by light shortage. Adding artificial lighting is not financially worthwhile.
  5. Well, my notes don’t include #5! It was something to do with appropriate crops, I think. Crops they can grow under shelters with no additional heating: spinach, baby kale, tatsoi, mustards, corn salad (mâche), claytonia, if T19 rowcovers are added for temperatures below 0°C (32°F). They use two layers of rowcover for temperatures below -5°C (23°F) and three layers below -10°C (14°F). They use minimal heating for chard, pak choy, Chinese cabbage, kale, lettuces, turnips, radishes, arugula, sorrel, celery, cilantro, parsley. You could consider soil-heating with PEX tubing filled with glycol (poisonous), 24″ (60 cm) deep in the soil, below cultivation level. At Quatre Temps they use above ground perforated polyethylene tubing in the pathways (it’s OK to step on it, it’s not high pressure).
Tatsoi at Twin Oaks ready for harvesting of whole plants.
Photo Pam Dawling

In the advanced session, we learned more details of their techniques and systems.

  • They start seeds for their winter crops in large cells (4″, 10 cm) so that they can keep their summer crops in the ground for 1-3 weeks longer. When they transplant these, they are careful about spacing, aiming to increase the light falling on each leaf. They plant the crops twice as close in the row, with double-wide spaces between rows, compared to warmer, more light-filled times of year.
  • They irrigate twice a week for 20 minutes, but I don’t know the flow rate of their driptape. From November to January they do not irrigate at all, as growth is so slow.
  • They fertilize in two doses, a little at planting time and more in February, using a mixture of compost, chicken manure and cotton meal, with the addition of feather mela in February. Bacterial activity increase with soil temperature. “Fertilizing cold soils is mysterious. . .”
  • Diseases in winter are mostly fungal. Use strong transplants, with a Rootshield dip before transplanting. They open the sidewalls every 4 hours to remove excess humidity and pay close attention to airflow. If needed, they use Contans.
  • Aphids survive at 5°F (-15°C). At 50°F (10°C) an adult female can create 20 offspring (per day?). At Quatre Temps, they use a three week winter break with no crops to freeze out their shelters. It gets down to -4°C (25°F). They disinfect in spring, removing all plant material, cleaning the structure itself with water and SaniDate (although it also kills beneficials).
  • For heating, a heat pump is very expensive but very efficient. An electric coil is less expensive. A climate battery (aerothermal energy) costs $20,000 and includes 24” (60 cm) diameter pipes deep in the soil, and a large fan. They use one to pre-heat air for the air-tube heating system. Something most of us can only dream about.
  • After the winter break, they direct sow new crops. To provide food for April, they plan gradual crop successions to bridge the gap between winter and spring. This also evens the workload.

Senposai is our star of Asian greens at Twin Oaks. Here’s a bed of senposai outdoors in spring. it grows really well in the winter hoophouse. Photo Kathryn SimmonsCrops they have been trialing include perennial sorrel, which regrows early (mid-Feb); celery and parsley (both very successful winter crops); Tokyo bekana, senposai and komatsuna (grow well in low light); green onions in fall and spring (don’t do well with light levels they get in winter); chrysanthemums regrow well, even in low light.