Growing peonies from seed takes three to five years to flower. It’s a long and careful process that is very rewarding when you finally see the flowers. Peony seeds are taken from the pods that develop after the flowers die off the plant. The pods hold many seeds and crack as the seeds ripen. You can start your seeds indoors or out, however the indoor treatment gives you a little more control over temperature and moisture, resulting in greater success. If you love peonies, it’s certainly worth the time to try to grow them from seed.
Planting Seeds Outdoors
Take seeds from pods as soon as the pods split. This is when the seed is ripe and ready for planting and should be planted right away.
Mix a few handfuls of compost into the flower bed and remove all weeds. The soil should be well-draining and the location should be in full sun to some afternoon shade.
Plant the seeds 2 1/2 inches deep and about 1 foot apart. More than one seed can be planted in one hole in case they all don't germinate. When they come up, you can separate them if more than one emerges.
Moisten the area well and cover with mulch. The seeds will need to go through the cold season to germinate. Mulch will hold in moisture and protect the seeds from frost heave. Mark the area where you planted the seeds and remove some of the mulch in the spring over the seed.
Water to keep the soil moist through the first growing season. You should see a small shoot come up from the ground. Mulch around the shoot again in the fall. The second season you should have a plant, and by the third or forth, you will have flowers.
Planting Seeds Indoors
Take the seeds from the pods as soon as they are ripe and rinse them with warm water. Place them in a bowl of warm water and soak them for four days. Change the water a few times a day and discard any seeds that become mushy.
Place the seeds in a plastic zipper-type bag with some moist vermiculite and zip shut. Place the bag in a very warm area, such as over your hot-water heater where the bag will stay at a temperature between 80 and 90 degrees Fahrenheit. Check the seeds every two weeks for moisture and to make sure they have not gotten mushy. Leave them in the warm area for three months.
Move the bag to an area where the temperature is between 50 and 60 F for a period of three weeks. By this time, you should start to see roots. Make sure the seeds stay just barely moist.
Place the bag in your refrigerator or another area that is around 40 F, once you see the roots start to develop. Keep the bag in the cool temperature until you start to see a leaf emerge from the root.
Take the small plant out of the bag and plant it in a small but deep pot filled with 1 part potting soil and 1 part compost. Water to moisten the soil and place in a filtered sun location. Plant the seedling outdoors in the spring and mulch.