Weed Management in Organic Farming
Hello friends, today we are here with a new topic called “weed management in organic farming“. Weeds can be considered a significant problem in agriculture because they decrease crop yields. Organic weed control is an approach to weed removal and prevention that does not involve the use of synthetic chemicals and weed killers. Some organic weed control strategies are cultural and mechanical methods, focusing on prevention, crop rotation, and cultivation. You can manage weeds in several ways such as through careful planning and planting and by using mulches.
Organic farmers use a different variety of tools to control weeds without synthetic chemicals. Successful organic farmers adapt their weed management as the weed population shifts. For effective weed management in organic systems, you must consider soil management, crop rotation, machinery, weather, and time and labor. The main principle behind organic weed control is that healthy soil promotes plant growth that controls the weeds. So, the first step of organic weed control is to test the soil to learn about any deficiencies, then naturally amends and soil fertilizes according to the soil test results. Then, with the inventions of herbicides, farmers have used these chemicals to eradicate weeds from their fields. By using herbicides not only reduced the labor required to remove weeds and also increased crop yields. Also, it has been found that in some cases herbicides use can cause some weed species to dominate fields because the weeds develop resistance to herbicides.
In organic farming, chemical herbicides cannot be used. So weeding can be done only manually. Cultural practices such as tillage, flooding, mulching can be used to manage the weeds. Also, the biological (pathogen) process can be used to manage the loss due to weeds. When the ground is fallow, a cover crop can be planted to suppress weeds and also build soil quality. By using drip irrigation weeds growth can be limited, and which restricts the distribution of water to the plant line.
A Step-by-Step Guide to Weed Management In Organic Farming
Why Do You Need To Control Weeds?
Weeds compete with your crops for light, moisture, nutrients, space, etc. They are very aggressive in doing so. Therefore, they can deprive crops of all these resources for a good yield.
- Weeds can reduce crop yield.
- They increase production and processing costs.
- Severe weed infestation can reduce the quality of the produce.
Simple Principles of Weed Control
The main principles of weed control are the basis for the development of several weed management methods. There are different ways to control weeds.
Smothering or burying – This is one of the simplest methods and good at killing annuals but not the best way to deal with perennials. Also, it brings other weed seeds up to the surface.
Sun – applies to everything from hand weeding through to most types of mechanical weeding and includes thermal mulching (it is the best and most powerful weed control in organics). Mechanical weeding benefits from the sun helping to dehydrate the weeds after they have been pulled up and killing them before they recover.
Competition – Generally, outcompeting weeds has the most potential as a method. Then, it leads to minimum man-hours, less tillage, less field being used (with more plants per square meter), and a better carbon footprint. Many combinations can be used like intercropping, bi-cropping, companion cropping, etc., as long as plants are complementary to each other.
Organic Weed Control Essentials
Before you start the organic process, understand that there are no quick fixes like you will find with spraying a quick synthetic chemical. Soil has a high level of synthetic chemicals lingering in it, is too wet, too dry, you are going to have a hard time setting it up for success. Then, it is a good idea to analyze it before you begin, solve any drainage problems, and get it into the proper pH level balance.
Grow crops in such a way that the weeds cannot get access to good soil, nutrients, sunlight, or growing space. Then, the desired plants can act as a barrier, fighting even when you are not around to help them out.
Watering on a Schedule – Watering your lawn too much can be tempting, but it is one of the fastest methods to end up with weeds, fungus, pests, and diseased grass. Know lawn watering needs, have the right tools for the job and gauge the needed frequency appropriately.
Use the Proper organic “Chemicals” – Some of the organic chemicals are vinegar and corn gluten meal and that can help to prevent weeds. Also, there are organic products available for purchases that take the place of synthetic chemicals. Along with that, many organic recipes exist for weed killers and pet-safe homemade herbicides.
Do not be afraid to get your hands dirty and there are several tools on the market that make the manual removal of even tough, spiky, and smelly weeds easy and painless. These methods are well more sophisticated than yanking out weeds by hand and need zero chemicals.
Weed Control Methods in Organic Farming
Some important cultural weed control methods are crop rotation, increasing the competitive crop ability, inclusion of green manure and cover crops, and intercropping. The ability of crops to compete against weeds can be increased by selecting the right crops and cultivars, considering the weeds present as well as the climate, ensuring rapid and uniform crop emergence through proper seedbed preparation, and also by using the right seed and seeding depth, increasing planting density. Some other cultural methods are adapting planting patterns wherever possible to crowd out weeds, and localized resource application, and optimum crop management like insect pest and disease management.
In case if you miss this: How To Grow Broccoli In Greenhouse.
The physical weed management practices are hand hoeing and weeding, digging, mowing, cutting, dredging and chaining, and mulching. One or a combination of these methods is used based on weed and crop situation. These methods to be discussed are water management, mulching, and solarization.
Some important thermal weed management methods are directed flaming, hot water, steam, microwave, ultraviolet radiation, electrocution, and freezing. Weeds can be killed by exposure to very low-temperature levels, for example, by exposing aquatic weeds to low air temperature levels by removing water from a pond or freezing terrestrial weeds using dry ice.
Mechanical weed control involves tillage and the cutting and pulling of weeds and is probably the oldest weed management tool. Some of the mechanical weed management methods are tillage, harrowing, and brush weeding is used at very early weed growth stages. Though some methods become difficult after the cotyledon stage and their selectivity decreases with increasing crop and weed age. So, if the weeds have become too large, an intensive and aggressive adjustment of the implements is necessary to control the weeds, and doing this increases the risk of damaging the crop severely.
The mechanical weed control method is critical for managing weeds in organic systems. It includes the use of pre-plant tillage such as plowing, disking, and field cultivating. Then, these types of primary and secondary tillage can help reduce the rate and spread of certain perennial weeds and kill emerged weed seedlings and bury weed seeds below the germination zone.
Planning Steps for Weed Management in Organic Farming
1. Know the Weeds
Obtain correct identification of the weeds present on the farm. Monitor fields regularly throughout the season. Absorb each weed’s life cycle, growth habit, the seasonal pattern of development and flowering, modes of reproduction and dispersal, seed dormancy and germination, and how the weed affects crop production. Find the weed’s weak points possibly the stages in its life cycle that are most vulnerable to control tactics and stresses to which the weed is sensitive, and these can be exploited in designing a management strategy.
Firstly “Know the weeds” because informs most of the succeeding steps. However, gaining a thorough knowledge of the farm’s weed is an ongoing process over many seasons that drive the year-to-year refinement of the farm’s weed management system.
Keep the weeds with crop rotations plan and implement diversified crop rotations that vary the timing, depth, frequency, and methods of tillage; timing and planting methods, cultivation, and harvest; as well as crop plant family. Schedule tillage and cultivation operations when they will do the most damage to the main weed species.
2. Crop Rotations
Crop rotation is the core of weed management in organic farming. The variation in crop species and planting times are necessary, as crop rotation creates a changing environment and prevents weed dominance of certain species. When making a crop production plan, farmers must design rotations for each field with weed species and potential problems in mind. Crops that are fast-growing and can out-compete weeds like winter squash, potatoes, sweet corn, and tomatoes are a smart addition to your rotation. Altering narrowly spaced plants with closely spaced crops, shallow-rooted with deep-rooted crops, cold with warm-season crops.
3. Design the Cropping System and Select Effective Weed Control Tools
Improve control strategies to address anticipated weed pressures in the farm’s major crops. Select the best cultivation implements like cost-effective pre-plant, between-row, and within-row weed removal. Though plan bed layout, as well as row- and plant spacing, to facilitate precision cultivation. Choose irrigation methods and some other cultural practices that are compatible with planned weed control operations.
Organic Weed Management Techniques
Start With Soil:
Before you start with the crops and the natural weed killer, it can be a good idea to analyze your soil. There are dozens of commercially available soil testing kits obtainable at major retailers that can help you understand everything from its composition its pH levels, to how much water it is going to hold. A different type of plant, flowers, and grasses requires different types of soil. Soil Fertility and Condition – In an organic system, it is very important to rely on the biological activity of the soil as the main source of fertility and favorable soil physical structure. An active and diverse soil microbial population is the key to growing healthy and high-yielding organic crops. Soils tests can be useful, but only if the results are interpreted appropriately for an organic system. Careful attention to the balance of key nutrients can reduce weed problems and enhance crop plant growth. The main mistake made by many organic farmers is the improper application of manure or improperly finished compost. This can throw off the balance of certain soil nutrients and microbial life and can increase weed growth. Some soil fertility amendments like gypsum can increase the looseness and tilth of the soil.
Soil nutrients, soil structure, pH, and composts:
Soil nutrients, pH level, and soil structure are not considered when it comes to organic weed management. This is in part because a key aim of organics is to ensure a healthy well-balanced soil so sub-optimal nutrients, pH level, and structure should not be a problem on organic farms. Moreover, in a well-designed organic system, other factors have a bigger effect on weed populations than soil nutrients and structure. However, if soil nutrients, pH level, or soil structure move too far away from optimum they can become the overriding cause of a weed problem, and unless they are addressed and other weed management techniques will have limited impact.
Some good mulch sources are wood chips, compost, grass clippings, and straw. And, be sure not to get hay, which can contain a lot of unwanted seeds. This is particularly helpful to do in your garden pathways before you put down gravel, stone, or wood chips.
Organic mulches are effective at stopping weeds from germinating. The ground to be mulched must be completely free of established weeds before applying the mulch, including dormant perennial weeds. If the un-mulched areas like the center grass strip contain creeping and spreading weeds, such as couch/twitch grasses these will often invade the mulched area and then spread very rapidly, due to the lack of competition. Such spreading weeds should be removed from the un-mulched area.
Mulches change in their ability to stop weed seeds that land on their surface example airborne seeds or seeds from the un-mulched areas, from germinating. It is possible to layer different types of mulch to take benefit of their different effects. Many organic materials like straw, leaves, pine needles, and wood chips, can be effective mulches. Straw and other materials that are easily decomposed are applied to vegetables during the growing season. Then, the mulch can be tilled in at the end of the season, where it will quickly decompose.
Green Manures and Cover Crops:
Green manures and cover crops can be useful for organic weed management. Then, they can be grown where there is a weed problem allowing the weeds to grow with them. Both are then grazed off by stock or cultivated into the soil before seeding occurs. Then, this reduces the weed seed bank, so fewer weeds germinate in the following crops. Green manures are very competitive and can weaken perennial weeds, and increase the time annuals take to reach maturity. Several short-term green manures coupled with the right cultivations can rapidly clean up a piece of land and improve humus content and nutrient levels.
Cover crops are being used to help control weeds after harvest and into early spring before planting crops. A healthy cover crop can help suppress weed growth by changing the soil dynamics, becoming established and growing quicker than weeds, and also by smothering weed seedlings. Also, some cover crops produce chemicals that are toxic to certain germinating seeds.
Solarization is the method of covering an area with clear plastic to heat the soil and kill weeds and seeds in the top 6 inches of soil. If solarization did properly, the use of chemicals to control weeds is not necessary. This only works in warm weather conditions where the heat will collect under the sheet and cook your weeds. Also, till the soil to bring weed seeds to the surface, and let them sprout just before solarizing.
Solarization can be an effective process of controlling many weeds such as Bermuda grass, bindweed, and other annual weeds. It can take several solarization attempts to eliminate them from the area. It can take a few more months before you are ready to plant, but not used chemicals to control these problem weeds.
Fertilize and Irrigate Carefully:
The number of nutrients and water will help weeds grow just as much as they will help the veggies and flowers you want. Only give your plants what they need. Fertilizing mainly provides an opportunity to apply some weed control. Use drip irrigation, irrigation bags, or olla pots to provide water only to the roots of plants, not the empty spaces around them. Give heavy feeders such as Squash, Tomatoes, and Cucumbers extra compost, but, feed crops like root vegetables much less.
Boil a kettle of water and then pour it over any weeds to burn them. This method is great for weeds growing in the cracks of pavement and coming up in your garden paths. The water will cool as it runs off so it won’t hurt plants you want to keep. Proper water management is an important factor in controlling weeds during production. By applying boiling water to weeds is one of the most cost-effective methods you can use to keep weeds.
You may also check this: Organic Vegetable Farming In Greenhouse.
Water Management to Control Weeds
Effective water management practices are key to control weeds. There are different ways that careful irrigation management can help to reduce weed pressure on crops;
1. Pre-germination of weeds – In this method, pre-germination irrigation or rainfall germinates weed seeds just before the crop is planted. Then, the newly germinated weeds can be killed by light cultivation.
2. Planting to moisture – Another method similar to pre-germination is planting to moisture. And, after weeds are killed, the top 2 to 3 inches of soil are allowed to dry and then form dust mulch. The dust mulch is pushed away and large-sized seeds can be planted into the zone of soil moisture at planting time.
3. Buried drip irrigation – Drip tape buried below the surface of the planting bed can provide moisture to the crop and also minimize the amount of moisture that is available to weeds closer to the surface. If properly managed, this method can provide significant weed control during the dry period.
Harvesting Requirements for Weed Management
The different harvesting requirements of crops can have a big impact on weed management. Many of the crops like peas or cereals do not require the soil to be disturbed for harvesting. Such crops allow the use of under sowing, usually, overwintering green manure or pasture mixture; so that once the crop is harvested the undersown plants are already established and will out-compete for the weeds. If under sowing is not used, direct drilling into the crop remains is possible or minimal cultivations followed by the drilling method. At the opposite extreme are root crops that involve the lifting and mixing of large quantities of soil. Then, this results in weed seeds being mixed through the soil profile which, together with the soil disturbance, will produce a greater weed strike than soils that have been undisturbed at harvest time. Potentially valuable weed management can be gained in weed susceptible crops by growing a crop that can be undersown the previous year and then using minimal, shallow, cultivations to destroy the undersown crop.
Tips for Effective Weed Management in Organic Farming
The selection of crop varieties is necessary to limit weeds and satisfy market needs. It is very important to consider planting disease-resistant varieties if certain pathogens are prevalent in the area. Deep shading crops also prevent the growth of many weed species.
“Blind cultivation” is mainly to destroy the weeds that can be growing within the rows and presenting direct competition to the crop. In this process, stir the top about 1 to 2 inches of soil, adding air and causing the millions of tiny germinating weed seeds to dry out and then die. Weed seedlings are vulnerable to drying out and to burying at this stage, and by doing an effective job of blind cultivation; you can achieve the biggest possible crop or weed size differential from the start. Though effective blind cultivation is done when the soil is dry and the sun is shining, a wind also improves the effect.
It is possible to prevent several weeds from being introduced onto the farm and to prevent existing weeds from producing large quantities of seed. The use of mowing weeds around the edges of fields or after harvest to prevent weeds from going to seed, and composting manure before the application can greatly reduce the introduction of weed seeds. Planting clean and high-quality seeds is essential to crop success. Some other sanitation factors to consider would include thorough cleaning of any machinery which might have been used in weedy fields, and the establishment of hedgerows to limit windblown seeds.