During World War II, labor shortages stretched the nation’s food production system to its limits. Americans were encouraged to harvest their own food by establishing “Victory Gardens” at their own homes. Twenty million Americans answered the call, growing fresh produce that helped the nation prevail through a difficult time. By 1944, historians estimate 20 million victory gardens were planted for a harvest of about eight million tons of food. This equaled more than 40 percent of all the fresh fruits and vegetables consumed in the United States, according to federal government statistics at the time.
Victory Gardens served another function, too: creating unity. Neighbors helped neighbors, sharing tips and extra produce. Families learned to become more self-reliant, lessening their impact on our industries and environment. The majority of Victory Gardens were likely organic! Growing a Victory Garden is a great way to sustain your family, community, and the planet through times of uncertainty. Compost is an essential ingredient to a successful Victory Garden, providing nutrients and organic matter to replenish tired soil.
Incorporating compost within the planting root zone in order to improve soil quality and plant growth applies to various types of vegetables, small fruits, herbs, and related items. Some of the benefits are:
- Improved soil structure,
- Nutrient savings – minimum 50%,
- Water savings – 25 – 50% annually,
- Reduction of plant loss, and
- May reduce pesticide usage through compost-induced disease suppression
- Compost should be uniformly applied over the planting area at an average depth of 1– 2 inches.
− Lower compost application rates may be necessary for salt sensitive crops or where compost possessing higher salt levels are used. An alternative is to heavily water after initial planting to leach potential excess salt from the crop’s root zone.
− May increase application rates (3-inch layer) in sandy soils and where reduced water usage is desired. Increased application rates are also suggested where medium and heavy feeding crops (e.g., tomatoes, broccoli) are established and where deeper soil incorporation (12-inch depth) is possible.
- Incorporate uniformly to a minimum depth of 6 inches using a rotary tiller or other appropriate equipment.
− Avoid incorporation when soils are excessively wet or dry.
− Deeper soil incorporation is preferred when growing crops like potatoes and carrots, whose edible parts are grown in the soil.
− NOTE: if creating a raised planting bed, establish a bed that can hold 12 inches of media depth, and place over soil that can drain. Compost can comprise up to 25 to 33% (by volume) of the media and should contain a similar volume of sand, bark fines, etc. which will allow drainage.
- pH adjusting agents (e.g., lime and sulfur) are important, where necessary, and may be applied in conjunction with compost incorporation. Preferably, do this a week before planting. Pre-plant fertilization may also be completed during this step, but higher nutrient compost may eliminate the need for pre-plant fertilization. Most vegetables require a soil pH of 6.0 to 7.0 and nitrogen requirements of 0.25 to 0.5 pound per 1,000 ft2 per season. Half of a crop’s nutrition is provided pre-planting, and the rest during the growing season.
− Depending on the crop and the compost, it may be possible to eliminate the addition of supplemental nutrition during crop production. However, this can be tricky, and is most easily accomplished in gardens where compost has been incorporated for 3 years in a row, and crops are not heavy feeders.
- Rake soil surface smooth prior to planting.
- The soil surface should be reasonably free of large clods, roots, stones greater than 2 inches, and other material which will interfere with planting and subsequent site maintenance.
- Water thoroughly after planting. Water and provide additional fertilization, as necessary, until the crop is harvested.
It is very similar in organic farming. Vegetable crops are well suited to the used of compost. Most vegetables are intensively cultivated and require high levels of nutrients and water. Moreover, most vegetables are produced in soils with low native organic matter. Compost can improve the overall soil fertility and available water status for vegetable production.
Farmers have found that the addition of compost allows them to reduce rates or fertilizers by as much as one third to half and still produce comparable yields. There can also be changes in crop growth and quality, such as less fruit cracking and more even ripening. In low input and organic production systems, the additions of compost can be the main source of external nutrients and a critically important factor in ensuring satisfactory crop yields and quality.
An advantage of using compost rather than animal manure (uncomposted) as soil amendment in vegetable production systems is consumer safety and biosecurity. Because compost undergoes sanitization under thermophilic temperatures, pathogens are largely destroyed and reduced to a level where they no longer pose a risk to public health.
Some of the key benefits of using compost in farms are:
- Nutrient savings – up to 50-100% savings on specific starter fertilizer nutrients (depending on crop requirements),
- Can replace organic matter volumes generated through cover cropping,
- May reduce or eliminate lime/gypsum application and,
- Research and field practical experience illustrates that the ongoing usage of compost
- Improves water holding capacity, reducing irrigation requirements,
- Increases cation exchange capacity, improving soil’s ability to retain nutrients,
- Reduces soil compaction and bulk density, providing fuel savings during tillage, and
- Enhances microbial processes, nutrient cycling to plants.
- Complete a soil test before applying compost, fertilizer, or other amendments to determine the requirements of the soil as they relate to the specific crops being grown and products.
- Uniformly apply compost throughout the field using a traditional manure spreader (flail/rear discharge or side discharge) or other specialized equipment, if available.
− Lower rates (4-8 ton/acre) of compost are typically used in multiple (successive) year applications as a nutrient supplement, organic matter source, and to improve water holding capacity.
− Higher application rates (10-20 tons/acre) are used to modify soil structure and other properties in a short-term.
- Existing soil conditions, compost characteristics and the nutrient requirements of the crop will influence appropriate compost application rates. Most often, compost rates are calculated based on the nitrogen or phosphorus requirements of the crop, with supplemental nitrogen or phosphorus applied to balance the ratio of nutrients that the crop needs.
- Thoroughly incorporate the compost to a depth of 8 to 10 inches using a disc or mole board plow, or other tillage equipment.
- Plant crop seeds, then irrigate based on plant needs, soil moisture, and climatic conditions.
Compost may also be applied over crop land managed using a no-till management style. In these cases, apply the compost over the crop stubble before drill seeding, and water it in when possible. For forage crops which may be harvested several times during a growing season, apply compost when the crop foliage is dry, so the compost can easily filter to the soil surface, and water it in when possible.
If you want to learn more, visit Victory Gardens – US Composting Council