by Sarah Dodd, CCMGA Master GardenerSeed Starting Essentials: Your Guide to Beginning Indoors
Embarking on the journey of starting seeds indoors is a pathway to a more bountiful garden and a deeply rewarding aspect of gardening. This comprehensive guide, developed from the insights of two detailed articles, aims to equip novice and seasoned gardeners with thorough knowledge and practical advice for successful indoor seed starting.
Selecting Seeds for Planting
Understanding Seed Quality and Variety
- Purity and Trueness to Type: Selecting the right seeds is crucial. Look for seeds free from contaminants and true to their specified cultivar. Quality seeds from a reliable dealer ensure good germination and healthy plant growth.
- Reading Seed Packages: Seed packages provide valuable information, including the type of plant, germination percentage, and any chemical treatments. This information is essential for planning and successful planting.
- Storage Recommendations: Proper storage of seeds is essential. Seeds should be kept in a cool, dry environment. Laminated foil packets offer excellent protection, but if you have paper packets, storing them in a tightly sealed jar or can is advisable.
Hybrid Seeds and Their Benefits
- Characteristics of Hybrid Seeds: Hybrid seeds are created by crossing different plant varieties. They often exhibit increased vigor, uniformity, better yields and sometimes have specific disease resistance or other unique cultural characteristics.
- Cost vs. Benefit Analysis: Although hybrid seeds can be more expensive, their benefits often justify the cost. Assess the advantages based on your gardening goals and preferences.
Saving Your Own Seeds
- Techniques and Considerations: Experienced gardeners may choose to save their own seeds, but this requires knowledge of proper selection, production, handling, and storage techniques.
- Cautions: Seed from hybrid plants typically does not breed true and should not be saved. Similarly, seeds from easily cross-pollinated plants like sweet corn, squash, and pumpkins, or those that can carry diseases like beans, should be approached with caution when saving.
Preparing Containers for Seed Sowing
- Container Selection: Choose clean, sturdy, and appropriately sized containers for the available growing space. Options include wood flats, fiber trays, plastic trays, clay pots, plastic pots, peat pots, compressed peat pellets, and various plastic flats and plugs.
Types of Containers and Their Uses
- Wood Flats, Fiber Trays, and Plastic Trays: Ideal for seeding plants that are easy to transplant. They save space and are suitable for later transplanting.
- Clay and Plastic Pots: Reusable and excellent for growing transplants. They require careful removal of the plant and soil ball at planting time.
- Peat Pots and Compressed Peat Pellets: These pots are biodegradable and can be planted directly into the garden, minimizing root disturbance.
- Sterilizing Containers: To prevent disease, sterilize used containers with one part chlorine bleach solution to ten parts water.
Soil Mixes and Other Growing Media
Choosing the Right Growing Medium
The ideal growing medium should be loose, well-drained, and of fine texture. Selecting or creating a mix that provides the right environment for seed germination and early growth is important.
Different Types of Growing Media
- Vermiculite: Alone, it provides good seed germination and is clean and sterile. Useful for covering seeds due to its non-crusting nature.
- Synthetic Mixtures: These soil-less mixes may contain peat moss, vermiculite, or perlite combinations. They require additional fertilization post-germination.
- Soil-Vermiculite Mix: A mix of garden soil and vermiculite can be effective but requires sterilization to eliminate pathogens.
- Soil-Peat-Sand Mix: Ideal for larger or more vigorous seeds. This mix also needs sterilization.
- Milled Sphagnum Moss: Prevents damping-off disease but requires prompt fertilization after germination.
- Layered Mixes: A combination of sterilized soil mix topped with a layer of vermiculite or milled sphagnum moss can be effective.
- Sterilizing Mixes: Sterilization of soil-containing mixes is crucial. This can be done by baking the soil in an oven at 200-220°F until it reaches an internal temperature of 160-180°F.
The Seed Sowing Process: Step-by-Step Guide
- Container Preparation: Fill your container with the chosen medium, leaving adequate space for watering and covering at the top.
- Sowing Seeds: Plant seeds according to package instructions. Do not cover fine seeds like petunias or begonias with soil.
- Watering Techniques: Use a fine mist or bottom watering to avoid disturbing the seeds and to help prevent disease.
- Creating the Right Environment: Cover the container to retain moisture and place it in a warm location, ideally with temperatures between 65-75°F for most plants.
- Monitoring Germination: Regularly check for germination and remove coverings once it's underway. Adjust coverings for seeds that germinate at different times.
Caring for Seedlings Post-Germination
Light, Temperature, and Moisture
- Light Requirements: Provide bright light immediately after germination. Use a combination of natural light and fluorescent lights if necessary.
- Temperature Control: Maintain appropriate temperatures, which vary depending on the plant species.
- Moisture and Watering: Balance is key. Keep the soil moist, but avoid over-watering.
Fertilization and Growth
- Initial Fertilization: Start with a diluted fertilizer solution soon after germination, especially for seedlings in artificial mixes.
- Regular Feeding: Continue fertilizing at regular intervals, following the recommendations for the fertilizer used.
Transplanting and Thinning Seedlings
When and How to Transplant
- Timing: Transplant seedlings after they develop their first set of true leaves and are large enough to handle.
- Transplanting Technique: Carefully dig up and separate the seedlings. Handle them by the leaves to avoid damage.
- Spacing: Adjust spacing based on the plant's growth rate and size.
- Aftercare: Continue similar care practices as in the seedling stage, ensuring adequate light, temperature control, and moisture.
Hardening Off Seedlings
A Gradual Acclimatization Process
- Gradual Exposure: Slowly acclimate seedlings to outdoor conditions over two weeks.
Techniques: Start in a shady area and gradually increase sunlight exposure. Adjust watering to slow growth but prevent wilting.
Planting Seedlings in the Garden
Transplanting Techniques and Tips
- Preparation: Prepare a planting hole about twice the size of the root ball. Maintain the same depth as the seedlings were in their containers.
- Planting: Carefully transplant, ensuring minimal root disturbance. Use a starter fertilizer solution to encourage initial growth.
- Special Considerations: For seedlings in non-biodegradable containers, remove them carefully. For biodegradable containers like peat pots, ensure the pot is entirely covered with soil to prevent drying.
Additional Considerations and Tips
Seed Storage, Disease Management, and More
- Proper Seed Storage: Store surplus seeds in a cool, dry place, ideally in a freezer, to extend their viability.
- Damping-Off Disease Management: Be vigilant for signs of this common fungal disease. Remove and treat infected plants immediately. Using soilless media and ensuring good drainage can help prevent it.
- Pinching for Bushier Growth: Pinching back the growing tips for annual flowers can encourage bushier growth. Avoid pinching vegetable plants.
- Enjoy the Process: Gardening is a learning experience. Embrace the joy and challenges it brings.
Starting seeds indoors is a fulfilling aspect of gardening, offering earlier blooms and harvests. This guide provides a foundation for gardeners to successfully navigate the process from seed selection to planting in the garden. Remember, each step is a learning opportunity, and the joy of gardening comes from successes and challenges.
Happy gardening!
Additional resources:
- Aggie Horticulture YouTube channel: How To Start Vegetables From Seed episode
- Aggie Horticulture YouTube channel: Saving Money When Shopping For Seeds
- Aggie Horticulture YouTube channel: Pre-germinating Seeds Indoors
- Earth-Kind guide to starting seeds by Texas Agricultural Extension Service
- Step-by-step guide with photos from the University of MD Extension
Sowing vegetable and annual flower seeds in the home general guide:
| Time to Seed Before Last Frost | Plant Types | Germination Time (Days) | Growth Rate | Cold & Frost Tolerance After Hardening | |||||||||
| VEGETABLES | |||||||||||||
| 10 weeks | Broccoli* | 6-10 | medium | good | |||||||||
| 10 weeks | Cabbage* | 6-10 | medium | good | |||||||||
| 10 weeks | Cauliflower* | 6-10 | medium | good | |||||||||
| 10 weeks | Head lettuce | 3-5 | medium | good | |||||||||
| 7 weeks | Tomato | 6-10 | medium | none | |||||||||
| 7 weeks | Eggplant | 7-14 | medium | none | |||||||||
| 7 weeks | Pepper | 7-14 | medium | none | |||||||||
| 4 weeks | Cucumber | 4-6 | fast | none | |||||||||
| 4 weeks | Cantaloupe | 4-6 | fast | none | |||||||||
| 4 weeks | Squash | 4-6 | fast | none | |||||||||
| 4 weeks | Watermelon | 4-6 | fast | none | |||||||||
| FLOWERS | |||||||||||||
| 14 weeks | Begonia | 10-12 | slow | none | |||||||||
| 14 weeks | Pansy | 6-10 | medium | good | |||||||||
| 14 weeks | Violet | 6-10 | medium | good | |||||||||
| 12 weeks | Lobelia | 15-20 | slow | none | |||||||||
| 12 weeks | Stocks | 10-14 | medium | good | |||||||||
| 11 weeks | Black-eyed Susan vine | 10-12 | slow-medium | none | |||||||||
| 11 weeks | Impatiens | 15-18 | medium | none | |||||||||
| 11 weeks | Torenia | 10-15 | medium | medium | |||||||||
| 10 weeks | Petunia | 6-12 | slow-medium | slight | |||||||||
| 9 weeks | Ageratum | 5-8 | medium | none | |||||||||
| 9 weeks | Scabiosa | 8-12 | medium | slight | |||||||||
| 9 weeks | Snapdragon | 7-12 | medium | medium | |||||||||
| 9 weeks | Verbena | 12-20 | medium | slight | |||||||||
| 8 weeks | Bells of Ireland | 21+ | medium | medium | |||||||||
| 8 weeks | Dianthus | 5-7 | medium | medium | |||||||||
| 8 weeks | Salpignlossis (Painted Tongue) | 8-10 | medium | none | |||||||||
| 8 weeks | Vinca (Periwinkle) | 10-15 | medium | none | |||||||||
| 8 weeks | Scarlet Sage (Salvia) | 12-15 | medium | none | |||||||||
| 8 weeks | Statice | 15-20 | medium | slight | |||||||||
| 7 weeks | Nicotiana | 10-15 | medium | slight | |||||||||
| 7 weeks | Nierembergia | 10-15 | medium | slight | |||||||||
| 7 weeks | Phlox, Annual | 6-10 | medium-fast | none | |||||||||
| 7 weeks | Sweet Alyssum | 4-8 | fast | slight | |||||||||
| 6 weeks | Aster | 8-10 | medium | slight | |||||||||
| 6 weeks | Balsam | 6-8 | medium-fast | none | |||||||||
| 6 weeks | Celosia (co*ckscomb) | 6-10 | fast | none | |||||||||
| 6 weeks | Cornflower | 6-10 | fast | good | |||||||||
| 6 weeks | Marigold | 5-7 | fast | none | |||||||||
| 6 weeks | Portulaca | 6-10 | fast | none | |||||||||
| 4 weeks | Cosmos | 5 | fast | none | |||||||||
| 4 weeks | Zinnia | 5-7 | fast | none | |||||||||
*Note: These vegetables are commonly grown as fall crops as well as spring/summer transplants. Start seeds 5-7 weeks (7-9 weeks for cauliflower) before plant out date. Planting out date depends on length of season for your particular cultivar and the date of first frost for your location.
Find out your frost dates by zipcode: https://garden.org/apps/frost-dates
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Insights, advice, suggestions, feedback and comments from experts
Starting seeds indoors is a popular practice among gardeners as it allows for earlier blooms and harvests. In this comprehensive guide, we will explore the key concepts related to seed starting indoors, as outlined in the article "Seed Starting Indoors: A Beginners Guide" by Sarah Dodd, a CCMGA Master Gardener.
Selecting Seeds for Planting
When selecting seeds for planting, it is crucial to choose seeds that are free from contaminants and true to their specified cultivar. Quality seeds from a reliable dealer ensure good germination and healthy plant growth. Seed packages provide valuable information, including the type of plant, germination percentage, and any chemical treatments. Proper storage of seeds in a cool, dry environment is also essential for maintaining their viability [[1]].
Hybrid Seeds and Their Benefits
Hybrid seeds are created by crossing different plant varieties. They often exhibit increased vigor, uniformity, better yields, and sometimes have specific disease resistance or other unique cultural characteristics. While hybrid seeds can be more expensive, their benefits often justify the cost. It is important to assess the advantages based on your gardening goals and preferences [[2]].
Saving Your Own Seeds
Experienced gardeners may choose to save their own seeds, but this requires knowledge of proper selection, production, handling, and storage techniques. It is important to note that seed from hybrid plants typically does not breed true and should not be saved. Similarly, seeds from easily cross-pollinated plants or those that can carry diseases should be approached with caution when saving [[3]].
Preparing Containers for Seed Sowing
Choosing the right containers for seed sowing is essential. Options include wood flats, fiber trays, plastic trays, clay pots, plastic pots, peat pots, compressed peat pellets, and various plastic flats and plugs. It is important to select clean, sturdy, and appropriately sized containers for the available growing space. Sterilizing used containers with a chlorine bleach solution is recommended to prevent disease [[4]].
Soil Mixes and Other Growing Media
The ideal growing medium for seed starting should be loose, well-drained, and of fine texture. Different types of growing media can be used, such as vermiculite, synthetic mixtures (containing peat moss, vermiculite, or perlite combinations), soil-vermiculite mix, soil-peat-sand mix, milled sphagnum moss, and layered mixes. Sterilization of soil-containing mixes is crucial to eliminate pathogens [[5]].
The Seed Sowing Process: Step-by-Step Guide
The seed sowing process involves container preparation, sowing seeds according to package instructions, watering techniques, creating the right environment, monitoring germination, and caring for seedlings post-germination. It is important to provide adequate light, maintain appropriate temperatures, balance moisture and watering, and provide initial fertilization and regular feeding [[6]].
Transplanting and Thinning Seedlings
Transplanting seedlings should be done after they develop their first set of true leaves and are large enough to handle. Carefully dig up and separate the seedlings, handling them by the leaves to avoid damage. Adjust spacing based on the plant's growth rate and size. Aftercare involves ensuring adequate light, temperature control, and moisture [[7]].
Hardening Off Seedlings
Hardening off seedlings is a gradual acclimatization process that involves slowly exposing them to outdoor conditions over two weeks. Start in a shady area and gradually increase sunlight exposure. Adjust watering to slow growth but prevent wilting [[8]].
Planting Seedlings in the Garden
When planting seedlings in the garden, prepare a planting hole about twice the size of the root ball and maintain the same depth as the seedlings were in their containers. Carefully transplant, ensuring minimal root disturbance. Special considerations should be taken for seedlings in non-biodegradable containers or biodegradable containers like peat pots [[9]].
Additional Considerations and Tips
Proper seed storage in a cool, dry place is important for extending their viability. Vigilance for signs of damping-off disease is crucial, and infected plants should be removed and treated immediately. Pinching back the growing tips for annual flowers can encourage bushier growth. It is important to embrace the joy and challenges of gardening as a learning experience [[10]].
This guide provides a foundation for gardeners to successfully navigate the process of starting seeds indoors. Each step is a learning opportunity, and the joy of gardening comes from successes and challenges. Happy gardening!
Note: The information provided above is based on the article "Seed Starting Indoors: A Beginners Guide" by Sarah Dodd, a CCMGA Master Gardener.
