Rhubarb seeds are covered in a paper-like shell. Soaking the seeds for 1-2 hours before planting will prepare them for germination so that they begin rooting sooner.
Use a small, 2-3 inch (5-8 cm) pot or starter tray with drainage holes on the bottom. Fill the pots or trays with your favorite seed starting soil mixture. Using your finger, dig a small hole about ½ inch (1.2 cm) deep. Place 2 seeds in the hole, then cover them with dirt and gently water in.
Keep your seed trays warm, about 70 degrees F is best for Rhubarb. Keep your trays covered with a humidity dome and spritz often so your seeds don't dry out, but remove the dome when your seedlings pop through.
When your seedlings are about 4-6", start to harden off your plants by taking them outside little by little to get used to the sun, rain, and cold before exposing them to the elements permanently and planting in your garden beds.
Rhubarb, Rhuem rhabarbarum
Pollination, insect; Life Cycle, perennial; Isolation Distance, n/a
While you can save rhubarb seed, most gardeners cut the flowers off in order redirect the energy that would be spent on seed production into vegetative and root growth. Saving seed is not recommended until the plant is at least three years old and well established, and even then, they will not likely grow true to type. That can be part of the fun though, seeing what you will get, because it will surely still be delicious! If you want to collect seeds, let the center flower grow tall. When the seeds have turned dry and flaky, cut the stalks off and separate the seeds by shaking. Propagation can also be achieved by splitting the mature crowns when the plants are dormant.