38 Seeds You Should Freeze Before Planting for Better Germination

There are certain seeds in the plant kingdom that you should freeze to avoid a poor germination rate after planting and if you are wondering why, read below!

It is a process that seeds undergo to mimic the winter for breaking their dormancy to kickstart germination. It’s especially crucial for plants native to cooler climates.

Artificially, gardeners can replicate this process using refrigeration. Please note that the stratification periods vary in duration; some seeds may require a few weeks to several months of cold exposure.

Duration: 4-8 weeks

Once done, you can plant the seeds indoors or outdoors when the weather warms up a bit.

Duration: 4-12 weeks

Cold stratification helps in ensuring the successful germination of Viburnum seeds. Studies have shown that stratified seeds generally exhibit higher germination rates.

Duration: 8 weeks

After the freezing process, soaking the seeds for 4 hours before stratification (lightly scratching the seed coat) can be helpful to rehydrate them and improve germination rates.

Duration: 4-6 weeks

If you start this 6 to 8 weeks before the last frost, it will be a good strategy for outdoor planting.

Duration: 5 to 8 weeks

Different Redbud species may have slightly different dormancy requirements. Some, like Eastern Redbud, may require longer stratification periods (up to 8 weeks).

Duration: Around 6-8 weeks (some may not require)

After stratification, sow the seeds in damp sand, vermiculite, or a mixture of perlite and peat moss.

Duration: 8-12 weeks

After the cold treatment, sow them outdoors at temperatures above 40 °F (4 °C).

Duration: A day in the freezer followed by 12-24 hours soaking in water.

If planting seeds indoors, starting 6 weeks before the last frost is recommended for optimal development