Starting Geraniums From Seed.
Geraniums (Pelargonium) are easily started from seed by following these simple steps:
Geraniums will bloom 12-15 weeks from the day the seed is sown. Check with your local county extension office for the last frost date in your area. Count backwards from that date to determine your ideal start date, (usually the end of January-February.)
I have had the best germination by presoaking the seeds. Wet two paper towels and lay out the seed in-between the two layers. Let set 24 hours.
The biggest threat to seedling survival is a fungus called damping off. To help guard against this disease select containers that are clean. If you are using used containers sterilize them in a bleach solution of one part bleach and nine parts water.
Select a commercially made light weight potting mix. Or, I have had success by simply using seed starting pellets. You can find these wherever garden seeds are sold. They are inexpensive and make transplanting simple. Presoak the pellets in water. Within thirty minutes they will have swollen to almost triple their size. Place them in trays or plastic saucers.
Place one presoaked seed in each pellet. If you are planting in potting mix sow seed 2-3 inches apart in pre moistened soil. Cover seed with a thin layer of potting mix or vermiculite (approximately 1/8 inch.) Cover the seeds with glass or clear plastic wrap. If you use wrap secure it so it will not sag in the middle.
Place in bright but indirect light. Ideal germination temperature is approximately75 degrees. Do not place container in direct light as this would cause excessive temperatures that would harm seedlings. Keep soil or pellets moist but not wet. A plant mister would work well for seed trays. Or place a small amount of water in the trays that the pellets are in. Allow water to stay in tray no more than 30 minutes.
Seeds will germinate in 5-7 days. Remove the plastic wrap or glass at this time. Transplant seedlings when the first set of true leaves appear. The seedling stems break very easily so be sure to handle the seedlings by the leaves and not their stems. If you have sown the seeds in pellets you can allow the seedlings to grow a little longer before transplanting. I waited until the root systems were well developed and showing through the mesh (see photo.)
Use a good quality potting mix and choose pots with drainage holes when transplanting. If you have used seed pellets simply place plant, pellet and all into the new container filled with potting mix. Plant seedling at the same depth as the top of the seed pellet.
Place seedlings under florescent lighting preferably within 6 inches of the seedlings. Plants will become tall and spindly if they have insufficient lighting. If artificial light is unavailable place plants in a bright east or south facing window. Turn the containers daily to encourage straight stems. Pinch out new grow tips from the center of the plants to encourage branching. Ideal growing temperatures at this point are 70-75 degrees in day light hours and 60-65 degrees night time. You will have best results with a minimum of 12 hours of light per day.
Water when soil has just begun to dry out. Never leave seedlings standing in water. Begin fertilizing weekly with a one quarter strength water soluble houseplant fertilizer.
Plants need to be “hardened off” before they can be placed outside.
Here’s how;
After the last frost date place plants out doors for no more than 5-8 hours per day then return them inside. Repeat this process for 7-10 days. Check daily that the soil is relatively moist because they will dry out quickly outdoors.
This takes a little effort on your part but you will have a higher rate of success. Geraniums will bloom all summer in most areas. If you live in zone 7 and above I have had some success mulching the top of my Geranium planters and placing them in an area where they receive morning sun and afternoon shade.
Enjoy!
