Biochar Workshop Part 5, Biochar & the Greenhouse

Biochar Utilization in Greenhouse Production

Introduction to Biochar Usage

• The greenhouse employs biochar in various forms, including an inoculant and Char Grow concentrate for seedlings, resulting in healthy plants and high yields.

• Approximately 8 tons of charcoal per acre is mixed into compost, enhancing the growth medium for seedlings.

Compost Tea Application

• Limited applications of compost tea were made this year due to weather conditions; only 11 applications occurred compared to previous years.

• Plants have been producing continuously since early May, with significant harvests noted even after thorough picking.

Plant Growth and Yield Observations

• The plants reached impressive heights (around 5.5 feet), showcasing exceptional production levels throughout the season.

• Mountain Fresh Plus tomatoes yielded 21.12 lbs per plant, characterized by nearly perfect fruit quality despite pest pressures.

Pest Management Strategies

• A wait-and-see approach was adopted for pest control; spider mites and whiteflies were present but did not significantly impact yield.

• Research indicates that stress from pests can increase antioxidant levels in produce, potentially enhancing nutritional value.

Soil Composition and Fertility Insights

• The soil's cation exchange capacity (CEC) was measured at 21.5, comparable to native prairie soils, indicating strong fertility.

Calcium Deficiency and Mineral Balancing in Soil

Understanding Mineral Balancing Theories

• Discussion on calcium deficiency observed through soil tests, referencing mineral balancing theories popularized by Acres conference attendees.

• Mention of Mark Shck's presentation at the Acres conference, where he struggled to prove the significance of mineral balancing in mountainous regions.

Soil Composition Insights

• Ideal soil composition suggested: mid 60% for calcium and high teens for magnesium; current levels noted as 55% calcium and mid-teens magnesium.

• Resulting issues with summer squash production attributed to mineral imbalance, leading to numerous immature fruits and blossom end rot.

Crop Performance Observations

• Despite squash issues, other crops have shown exceptional productivity; specific mention of Italian parsley thriving despite bolting.

• Hypothesis that fruiting needs of squash are linked to calcium deficiency affecting growth patterns.

Cover Cropping Strategies

• Introduction of oil seed radish and filia taneda folium as cover crops aimed at improving soil structure and biodiversity.

• Explanation of the rationale behind using deep-rooted plants due to initial compaction concerns from greenhouse construction.

Greenhouse Management Techniques

• Description of greenhouse setup including computer-controlled curtains for heat retention; ongoing evaluation before implementing radiant heating systems.

How to Manage Soil Health and Disease in Organic Farming

Bed Preparation and Soil Mixing Techniques

• The beds were prepared by hand, but a power harrow was used to apply compost on top of the char. This method did not mix the materials thoroughly.

• The team relied on microbes and worms for further mixing over time, aiming for low to no tillage practices to maintain soil health.

• While they generally avoid tilling, certain crops like carrots may require more intensive mixing methods.

Disease Management Strategies

• The discussion highlights the absence of late blight in their crops, attributed partly to an effective spray program.

• A previous year saw only 3% eggplant loss due to disease; proactive measures included ordering bioactive fungicides that were ultimately unnecessary as soil diversity helped control the issue.

Understanding Soil Pathogens

• Cucumber diseases such as CCE can devastate crops; however, high soil diversity slowed its progression significantly compared to typical cases where plants die quickly.

• There is a debate about whether organic growers experience fewer issues with diseases due to intentional practices that enhance soil health.

Proactive Measures Against Diseases

• Despite nearby commercial farms suffering from late blight after flooding, this farm managed to avoid infection through careful monitoring and removal of affected plants.

• Various products were utilized for disease management including Serenade and Double Nickel, which bolster plant defenses rather than directly killing pathogens.

Genetic Resistance and Crop Selection

• The choice of genetically resistant varieties plays a crucial role in successful organic farming; reliance on specific genetics from NCSU has proven beneficial.

Cucumber and Tomato Production Insights

Ongoing Crop Production

• The speaker notes that cucumbers have been producing continuously since early June, surprising given the time elapsed.

• Despite challenges like white fly and spider mite pressure, the fertility of the soil is credited for ongoing production.

• Initial crops were planted in late January, with tomatoes added in March, showcasing an earlier planting schedule compared to previous years.

Soil Fertility and Plant Growth

• The speaker emphasizes the rapid increase in soil fertility achieved through specific practices, leading to robust tomato growth since April.

• Tomatoes experienced a temporary halt in production but are now flourishing again; plans are made to prevent freezing to maximize yield.

Plant Management Techniques

• A new method involving cables will be implemented next year to support plant growth and prevent them from falling over due to height.

• Various tomato varieties are discussed, including Smarty and Mountain Magic, which exhibit resistance to pests while maintaining high productivity.

Pest Resistance Strategies

• The use of resistant tomato genetics is highlighted as a successful strategy against pest pressures like white flies and spider mites.

• Continuous production despite pest issues indicates effective management strategies employed by the growers.

Winter Crop Planning

Current Crop Status

• Italian parsley has grown significantly; peppers are nearing removal due to their height but remain for observation purposes.

Soil Management Innovations

• A low-till approach is being used where cover crops were scalped before applying compost tea, creating a suitable seedbed without traditional tilling methods.

Future Planting Plans

• Plans include direct seeding carrots after Thanksgiving along with beets and turnips while also preparing beds for winter greens.

Greenhouse Innovations and Crop Management

Cover Crops and Heat Management

• The plan includes using cover crops in a section of the greenhouse, aiming to grow heat-sensitive winter crops while minimizing heating costs.

• The philosophy shared among the team emphasizes efficient use of generated heat, avoiding waste by finding innovative ways to utilize it.

• There is an ongoing effort to harness solar energy for heating, with discussions on how to optimize heat usage throughout the greenhouse.

Experimentation with Fruit Crops

• The discussion highlights the potential for growing early crops like raspberries in heated greenhouses after chilling them in coolers, allowing for harvest as early as February.

• Current challenges include dealing with pests (specifically "spot Wing dapa"), which has delayed plans for soft fruit cultivation until resolved.

Mushroom Cultivation Insights

• Previous experiments included growing oyster mushrooms in sterilized straw pots within the greenhouse, utilizing CO2 produced by fungi to benefit plant growth.

• Issues arose with maintaining moisture levels during warmer periods; thus, mushroom cultivation may be more suitable for winter months when conditions are cooler and more manageable.

Future Plans for Peppers and Other Crops

• Considerations are being made to experiment with overwintering pepper plants, which have shown increased production in their second year compared to their first year. This could involve using low tunnels or other protective measures during colder months.