Care Guide: Germinating Seeds
Living Care Information
Germinating Seeds
Quick Start Information
To ensure optimal germination rates, plant seeds the same year you receive them. Germination rates decrease over time.
You will need to purchase a germination medium for your seeds. We recommend Carolina® Seed Starter Mix and our Seed Starter Kit.
Store seeds in a cool, dry location and protect them from moisture.
About the Organism
- A seed consists of an embryonic plant and a food reserve surrounded by a seed coat.
- Germination is the process by which the embryonic plant begins to grow and break out of the seed coat as an individual plant.
- Before germination can begin, a seed must absorb water.
- Enzymes stored within the seed become functional, and the seedling begins to grow.
- The food reserve contained in the seed nourishes the embryonic plant until it is able to photosynthesize on its own.
- Domain: Eukarya
- Kingdom: Plantae
- Phylum: Various
- Class: Various
- Order: Various
- Family: Various
- Genus: Various
- Species: Various
Preparation
Seeds in sealed packets should remain viable and free of insect damage for a year or longer if properly stored. Always store seeds in a cool, dark location protected from moisture. Recommended storage temperature is 20° C (68° F). Temperatures below 12° C (54° F) may reduce viability of some seeds. Seed packets may be placed in a sealed glass or plastic container and stored in a refrigerator. As a general guideline, seeds should be used within a year of receipt when the germination rates are greatest. Seeds may still germinate after a year, but the rate at which viable plants emerge decreases over time and varies from species to species.
Housing
No housing information applies for this process.
Feeding
No feeding information applies for this process.
Maintaining and culturing
Never allow germinating seeds to dry out. Adequate moisture must be available to ensure proper germination. Inspect all containers daily. Most seeds will germinate at 24 to 26 °C (72 to 78° F), which is about room temperature. You can use thermostatically-controlled growth chambers, heating cables, or propagation mats to ensure a constant temperature. Most seeds will germinate in total darkness, although some plant species require light. Instructions for seeds requiring special treatment are usually provided on the package. If you have experienced molding of planted seeds, we recommend surface sterilization. Use one of these methods:
- Soak seeds in a 1:1 (volume) solution of 3% hydrogen peroxide and water or absolute ethanol and water for 10 minutes.
- Soak seeds in a 1:8 (volume) solution of 5.25% sodium hypochlorite (household bleach) and water for 10 to 15 minutes.
- Soak seeds in a 1% potassium permanganate solution for 20 minutes.
Follow the surface sterilization with at least two water rinses.
You can speed germination of large seeds such as corn, beans, and peas by soaking the seeds in water for 8 to 12 hours before planting them. Do not expose imbibed seeds excessively to air because drying may injure the now-active embryo. Sow very small seeds (such as coleus and tobacco) on the surface of moist planting medium and leave them uncovered or press lightly into the surface with a flat object (such as a wooden block) to ensure proper contact with the medium. Cover larger seeds (such as radish and tomato) with a thin layer of planting medium. To facilitate proper spacing of the seedlings, sow the seeds in shallow rows (drills) made by lightly pushing the long edge of a ruler or other sharp-edged stick into the soil surface. Cover very large seeds to a depth equal to the diameter of the seeds. Use a blunt stick (such as a pencil) to drill holes to the required depth. Drop seeds into the planting holes and cover them with soil. After planting the seeds, lightly mist or sprinkle the surface of the medium with water and then cover the container with clear plastic or glass to retain moisture during the germination process. Place the container in a location where the temperature can be maintained at 22 to 26° C (72 to 78° F). Light is usually not required during the germination process. However, some seeds (such as tobacco and coleus) will not germinate without light; special care instructions are given on the packet label of these seeds.
Disposal
Carolina provides living organisms for educational purposes only. As a general policy, we do not advocate the release of organisms into the environment. In some states, it is illegal to release organisms, even indigenous species, without a permit. The intention of these laws is to protect native wildlife and the environment.
We suggest that organisms be:
- Maintained in the classroom.
- Donated to another classroom or science department.
- With parental permission, adopted or taken home by students.
- Donated to a nature center or zoo.
Biosafety
No biosafety information applies for this organism.
Video
No video or video playlist applies for this organism.
FAQs
Why haven’t my seeds germinated?
Are the seeds fresh? Have they been properly stored? If you can answer yes to both questions, you may not have waited long enough, or the potting soil may lack moisture or be too moist. When pinched between thumb and index finger, the potting soil should be moist enough to clump but should not drip water. Also, small seeds are sometimes washed too deeply into the mix when top watering. Read any planting instructions on the seed packet as some seeds have special needs for germination.
My seeds germinated and the seedlings grew for a few days before falling over and dying. What went wrong?
The seedlings were killed by a fungal problem known as "dampening off." This condition is promoted by potting soil that is too moist, which allows fungal spores to grow.
My seeds have germinated but the seedlings are spindly and falling over. What do I do?
Seedlings respond to environmental stress by growing elongated, weak stems. The most common cause of stress is too little light. Increase the intensity of light or its duration or both. Other common causes of stress to seedlings are too much soil moisture and too much heat.
Need help?
We want you to have a good experience. Orders and replacements: 800.334.5551, then select Customer Service. Technical support and questions: caresheets@carolina.com
