Then move the seedlings to a bright location so they can continue to develop. Monitor temperature and moisture so that embryos and seedlings remain viable. After germination, temperature should be gradually lowered to 65 degrees F.
Choose a sterile, soilless potting media without fertilizer to start seeds. Sterile mixes are free of weed seeds and disease organisms. Weeds compete with the germinating seedlings for water and nutrients, and disease organisms can kill seedlings in the early stages of germination.
Avoid using garden soil as it is heavy, holds a tremendous amount of water, and often contains weed seeds or disease. A good seed-starting media will have a fine, even texture and be fairly uniform.
This will help maintain good contact of seed with media. You do not want a seed-starting media that is lumpy or chunky, especially when sowing small seeds Figure 4. There are several sterile, soilless materials from which to choose. Sand, perlite, vermiculite, and peat moss are readily available and can be mixed together to create a media that has good moisture-holding capacity and good drainage.
Sphagnum peat moss is often combined with perlite for a seed-starting media. A good recipe for making your own media includes 4 quarts shredded sphagnum peat moss, 4 quarts fine vermiculite, 1 tablespoons of superphosphate, and 2 tablespoons of ground limestone.
Mix thoroughly, then wet completely. Leave the soil to drain and do not plant for 5 to 6 days. This allows the lime to react with the peat moss and create a favorable environment for the seedlings.
Any container can be used for starting seeds as long as it drains, is deep enough for good root development, and is sanitized prior to use Figures 5a, 5b, and 5c. Plastic inserts, flats, and trays are available for purchase. Rectangular flats and trays are usually 12 to 18 inches long and often come with a clear, fitted dome or cover. You can make your own flats from wood, but they are heavier than plastic flats and are more difficult to sanitize for reuse. Be sure to leave gaps between the slats, or drill holes in the bottom, for drainage.
You can fill the flat directly with media, or use an insert or smaller container set into the flat and filled with media. Growing seedlings in individual cells or containers reduces damage to roots and shock to the seedling when later transplanted into the garden or another container. You can also make your own containers from recycled materials, such as plastic salad boxes and muffin containers, as long as good drainage is provided and there is adequate depth for root development.
The clear plastic containers are like mini greenhouses. When the lids are closed, an ideal high-humidity environment is created for germinating seeds. As the seedlings emerge and grow, the lid can be gradually opened and removed. Pots can also be made from recycled newspaper using a can or bottle as a form, or soil blocks can be made with an initial investment in a molding device. Additionally, seeds can be started in hydrated peat pellets for easy transplant into the garden Figure 6.
For more information on usine peat pellets, view or print the "Starting Plants From Seed using Peat Pellets" information sheet. Sanitation is critical in the germination process. Disease causing fungi can attack seedlings and kill them at this early stage.
To reduce chance of fungal attack, use sterile media and sanitized containers. To sanitize used containers, wash to remove any soil or debris and rinse with a solution of one part chlorine bleach to nine parts water.
Rinse thoroughly with clean water. Providing appropriate air and media temperatures as well as adequate moisture and humidity is important to seed germination.
Choose a warm location that provides bright, indirect light and good air circulation. For best results, refer to the information on temperature previously mentioned in the section on germination. Seeds can be sown directly into the container or space where they will grow, or they can be transplanted to another container or space to finish growing.
Most seeds are planted at a depth approximately twice their diameter. Very small seeds should be simply pressed gently into the surface of the soil and barely covered. To raise the humidity for the germinating seeds, the container can be covered with plastic wrap or placed in a plastic bag, but remove the bag as soon as germination occurs. Once seeds germinate, you will need to provide supplemental light for proper seedling growth.
Light stands should position the lights within 2 to 3 inches of the seedlings. As the seedlings grow, raise the lights, but keep them 2 to 3 inches above the seedlings. Set a timer so that the lights are on 16 hours daily. As seedlings grow, raise the lights above the plants. Without supplemental light, plants will be weak and spindly, often stretching toward a window or other light source. Not all plants respond well to transplanting, and for some crops, such as beans, transplanting does not offer benefit enough to pursue.
Most large-seeded plants, such as corn and pumpkin, and root crops, such as carrots and beets, are best direct-seeded. Sow seeds directly into the container or place where they will grow, following the recommended seeding depth on the package. Species with small seeds can be more challenging to handle. Carefully prepare the seed bed so that it is smooth and even, and pay close attention during germination and initial growth of the seedlings.
Some seeds are started in a seed bed, transplanted to a secondary container for growth and development, and then transplanted to the container or place where they will grow and finish their life cycle. For example, tomatoes are germinated, transplanted to a flat, grown out for several weeks, and then planted in the garden after last frost. A seed bed may be a small container of seed-starting media, a flat filled with media, or a prepared bed in the garden though seedlings are at greater risk for insect and disease attack.
Seeds can be scattered across the top of the media or sown in rows Figure 7. Managing moisture during germination and at the seedling stage can be challenging. You want to keep the media moist so that the embryo does not dry out, but you do not want to overwater. Media that is too wet will cause seeds to rot or seedlings to die.
Remember to keep seed-starting media moist to the touch. While it sounds like a bit of extra work, there are several benefits to germinating seeds in preparation for transplanting. Ultimately, you will end up with the desired number of plants, as opposed to having too few or too many. By germinating in a seed bed and transplanting to the desired flat or container, you do not waste valuable space in your propagation area with containers where seed has not germinated.
If you are working with seed whose viability is declining, you can sow extra seed in a seed bed and transplant what actually germinates and is vigorous. This also gives you an indication of when the seed are no longer viable and ready for discard. Growing transplants allows you to make the most of the growing season by having plants ready at the best time for planting outdoors. If you are sowing seeds to grow transplants, timing is an important consideration.
The optimal temperature for growing seedlings may be different from that for seeds Table 2. Remember, optimal temperature will stimulate optimal growth. You can control temperature to control plant height. Cooler temperatures generally slow down growth, and warmer ones speed up growth.
It is still critical to maintain good air circulation and sufficient moisture. Generally, watering should be deeper to accommodate developing root systems. You may need to use different wand or hose heads to water seeds and seedlings because each use different amounts of water.
Remember to carefully monitor and water the plants at the edges of flats. They dry out faster than those in the middle. However, overwatering can increase the probability of plants developing damping off. This final step before seedlings are planted in the field gradually exposes them to the conditions they will have in the field.
This process stimulates the plants to accumulate carbohydrate and nutrient reserves and strong cell walls by exposing the plants to day and night temperature fluctuations, increased air movement and wind, reduced watering, and full light. Hardening off transplants is important, especially if they are to be planted under stressful early season conditions.
Most transplants may be hardened off by reducing the temperature in the greenhouse through ventilation. Reduced watering will also provide some hardening effect. Do not let plants wilt excessively. Do not harden off transplants by reducing fertilizer application, as this often results in stunted plants that do not establish well in the field. Some growers will put plants outside for days prior to planting. This allows the plant to become acclimated to outside conditions while still in the flat.
Plants hardened off in this manner often have improved field performance as compared to those planted directly from the greenhouse Garton, Sikkema, Tomecek The National Organic Standards require that producers use organically grown seeds, annual seedlings, and planting stock.
Nonorganically produced, untreated seeds and planting stock may be used to produce an organic crop when an equivalent organically produced variety is not commercially available.
There is no allowance for seed treated with prohibited materials. Captan, thimet, and similar chemical fungicides are not on the national list and are not permitted. Please take this seriously. If your seed is covered in a pink or orange powder, it is probably prohibited. We may not be able to certify your crop if you use seed treated with prohibited materials. The first step is to determine whether an equivalent organically produced variety is available.
By equivalent variety, look for comparable growing habits, days to maturity, insect and disease resistance, flavor, and other important qualities. If a suitable organic equivalent variety is not available, document where you tried to look for organic seed, as that is important for your certification records. Once you have found a source for a specific equivalent organic seed, the next step in determining commercial availability is to see if it is of the appropriate form, quality, and quantity.
Compliance is reviewed in the context of the organic system plan, which is verified during the annual inspection. A pattern of inadequate documentation and lack of good faith effort to obtain organically grown seeds and planting stock may be considered noncompliance and might result in Pennsylvania Certified Organic requiring prior approval regarding commercial availability issues in future planting cycles.
Listed below are a number of sources for organic seed provided by Pennsylvania Certified Organic For a more complete listing including forage, field crop, and cover crop seed and transplants, go to the Pennsylvania Certified Organic website. Fred C. Gloeckner and Co. Gardens Alive! Garton, R. Sikkema, and E. Kemble, J. Alabama Cooperative Extension, Mackean, D. Maynard, D. Knott's Handbook for Vegetable Growers. Hoboken, N. Miles, A. Pennsylvania Certified Organic.
Pennsylvania Heirloom Seed Savers Club. Raven, P. Ray, and S. Biology of Plants. New York: W. Freeman, Seed Technology Educational Programs. Prepared by S. Let's Stay Connected. By entering your email, you consent to receive communications from Penn State Extension. View our privacy policy. Over the past 7 years, Ms. Jolie Goh has been proficient in showing her students how to apply scientific concepts to everyday phenomena while equipping them with the ability to relate once complicated scenarios to simple solutions.
This has helped to inculcate the development of logic and critical thinking skills for her students. Jolie strives to achieve the amalgamation of academic excellence and essential life skills in her classroom. With patience and encouragement, she aims to foster confidence in her students and guide them through challenging topics and questions using proven methods. You must be logged in to post a comment. When discussing the movement of food within a plant, there are a few questions we need to ask ourselves: Which stage is the plant at?
Has the plant developed its true leaves or does it still depend on its seed leaves for food? Today, I will be helping you to gain a better understanding of the movement of food within the plant: During the seedling stage before the true leaves are formed At the young plant stage where the plant has developed its true leaves.
If you like our methodology, we've some upcoming workshops:. About The Author. Jolie Goh Over the past 7 years, Ms. Related Posts.
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