Do your seeds require stratification (pre-treatment)?
Stratification is required for most seeds but not all. Most pine, spruce, cypress, elm, some oak, and other seeds do not require any pre-treatment. Listed below are the stratification requirements for each seed we sell - listed by category in alphabetical order.
If your seeds do not require stratification/pre-treatment: You can plant your seeds indoors anytime during the year and outdoors in the spring (after the last frost in your area). This is usually after May 15 in most US states and Canada.
If your seeds require stratification: The best time to stratify tree and shrub seeds is in the winter months. If the stratification requirement is: 60-120 days - you should start stratification in January or Feb. You can also put your seeds in the ground during the fall - in September or October (Before the ground freezes). If the ground freezes in your area during the winter months - then your seeds will germinate (sprout) in the spring after the last frost in your area.
How to: Cold Moist Stratification:
If your seeds require cold moist stratification: You are mimicking the natural winter cycle for seeds. Most seeds fall during the fall months (September to November), then go through winter under soil, leaves and snow. The seed will not germinate until the weather is in the seeds favor to grow. The outdoor growing season for tree and shrub seeds is: May to October. This gives the seedling enough time to grow strong enough to survive the winter weather conditions.
Stratification Supplies: You will need ziplock bags and Jiffy Seed Starting Mix.
Instructions: Fill a ziplock bag half way with seed starting mix. Add 10-20 seeds (depending on the size of the seed - less for acorns). Shake the bag a few times to make sure the seeds are covered with soil. Add water to keep moist. Place the bag in the bottom drawer of your fridge. Check on your bag once a week to see if you need to add more water to keep the soil moist.
Cold Stratification: Cold stratification requires placing your seeds in your fridge in a ziplock bag or container - without the moist seed starting mix.
Warm Stratification: What if my seeds require a warm stratification period first? Some seeds such as the White Fringe and Holly - require warm stratification and then cold moist stratification. The warm stratification is required before you start the cold moist stratification. Your seeds will need to be in moist soil in temps of 70-75 degrees for the required time. You can achieve this by filling plastic containers with seed starting mix. Place the seeds barely underneath the top of the soil. We use the dollar store plastic containers. Place the containers on a heat seedling starter mat.
What do I do after the stratification period is finished? If your seeds are finished stratifying - you should plant your seeds immediately either indoors or outdoors. If the weather conditions outdoors are in favor of your seeds then you can plant outdoors either in the ground or in pots/containers. Use seed starting mix. If you are starting your seeds indoors - make sure you have a heat seedling starter mat and a growing light. Tree and shrub seeds are not like vegetable seeds. They are more hardy than vegetable seeds and require direct light/heat to germinate. Most tree seeds will not germinate in a paper cup on the window sill. If your seeds have been stratifying naturally outdoors during the winter - then they will naturally germinate during the spring season.
Other Pre-Treatment Requirements:
Scarification: Some seeds have very hard seed coats and require scarification. Seeds such as Yellowhorn and Redbud require scarification. Scarification is breaking through the seed coat to allow moisture inside the seed embryo. You can achieve this by rubbing your seeds in-between course sandpaper for a few minutes. You can also line a mason jar with sandpaper, add the seeds and shake for 5 minutes. This will help 'nick' the seed coats. Then soak your seeds in water for 24-48 hours.
High Humidity Germination: (Also called 'Sow Under Glass').
The following seeds require high humidity to germinate: Quaking Aspen, Royal Empress and Sourwood.
Supplies Required: Growing Light, Heat Seedling Starter Mat, Jiffy Seed Starting Mix, Spray Bottle filled with water, Clear salad bowl with lid.
1. Poke a few holes in the lid of the salad bowl.
2. Fill the bowl less than half way with Jiffy Seed Starting Mix.
3. Add water to keep the soil mix moist. Then spray the inside of the container lid and walls with water.
4. Sprinkle 10-20 seeds on the top of the soil mix. You don't need to bury the seeds in the soil or cover the seeds with soil.
5. Place the salad bowl on the heat mat 24 hours a day and under the growing light for 12-14 hours per day.
Your seeds will germinate (sprout) in about 1 week. Watch out for mold forming on the soil. This can happen in a high moisture environment. Mold usually occurs due to over-watering. Keep the soil moist - not soaking wet. Once your seeds sprout - pluck each seed from the bowl and place each seed into its own pot/container. Keep the containers under the growing light and on the heat mat until they are at least 3-6 inches tall. These seeds are tiny so barely cover the seeds with the soil mix. If mold starts before the seeds germinate then pluck the seeds from the soil and start again in a new clean salad bowl.
*Some people prefer to use the plastic vegetable seed growing domes sold in garden stores. These domes are often to big and will not create the high amount of humidity and moisture for these tree seeds to germinate.
Planting tree and shrub seeds is easy and very rewarding once you get the hang of it! Do not over complicate it. Each seed does not have its own set of directions. All seeds are planted the same way. Seeds only need sun (light), heat (warmth) and water to grow into a healthy tree. Keep your supplies clean and don't over water your seeds/seedlings. Keep your seeds happy and they will do magical things for you - like grow into a strong healthy Tree.