How To Plant, Start and Grow Geranium Plants For Seeds

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Cheerful geraniums are popular with gardeners in all parts of the world.

These hardy flowering plants come in various colors, flower types, and scents.

Growing Geranium SeedsPin

It’s very easy to propagate geraniums from cuttings, but what can you do if you don’t have any mature parent plants nearby? 

Luckily, it is almost as easy to grow these lovely garden plants from seeds as cuttings. 


In this article, we show you how. 

14 Steps To Successfully Grow Geraniums From Seed  

1. Get An Early Start

The only downside to growing geraniums from seed is that it is rather time-consuming. 

It can take 3 – 4 months to get from seed to flowering plant.

Therefore, if you want to have plants ready to set out in the springtime, you will need to sow your seeds indoors, late in the winter. 

2. Use A Sterile, Soilless Seed Starting Mix

The best growing medium for geranium seed is a soilless mix, such as sphagnum peat moss with a bit of perlite or vermiculite thrown in to improve drainage.

In addition, a soilless mix gives you more control over potential damage caused by bacteria, viruses, fungi, and weeds. 

3. Keep It Clean

It is also advisable to use brand new containers or thoroughly sterilize any container you use.

If you are repurposing a planting container, be sure to wash it with dish soap and water and then soak it in a bleach solution for about 15 minutes. Learn about sterilizing pots without using bleach. Learn about sterilizing pots with using bleach.

Rinse and dry the container thoroughly, and make sure it has ample drainage holes. 

4. Prepare Your Container

  • Fill your clean container with a germination medium, leaving about an inch of space at the top.
  • Press the medium down lightly and then water it thoroughly.
  • Allow excess water to drain off. 

5. Leave Plenty Of Room For Seedlings To Grow

  • Sow your geranium seeds 1″ to 3″ inches apart.
  • Sprinkle about 1/8″ of an inch of growing medium over them.
  • Water again by either placing the growing container in a tub of water or gently spraying water over the surface of the medium. 
  • Drain off excess water and then cover the germination tray lightly with clear plastic wrap or a clear plastic cover. 

6. Provide Consistent Light And Warmth

  • Place the starting tray in an area that receives bright, indirect sunlight and maintains a steady temperature of 70° to 75° degrees Farhenheit.
  • Protect the seeds from harsh, direct sunlight and temperature extremes. 

If you don’t have bright, indirect sunlight, use artificial light entirely.



In truth, fluorescent lighting is preferable to natural sunlight from a window.

This is because fluorescent lighting is consistent and encourages strong, upward growth.

The lighting is inconsistent if you try to grow your young plants on a windowsill.

It comes from the side rather than above tends to cause leggy, spindly growth.

Also, you don’t have good control over the temperature on a windowsill. 

You should not need to water again until your seeds germinate.

Your seeds should begin to germinate within ten days if all goes well. 

7. Uncover Your Seedlings And Add More Light

When your seedlings have germinated, do the following steps:

  • Take off the plastic covering.
  • Add artificial light to boost the light in the young plants’ current setting. 
  • Fluorescent lighting should be placed between 4” and 6” inches above the little plants for a period of 12 to 16 hours daily.

It’s easy to set this up using a standard shop light fixture with two fluorescent tubes.

One should be a 40-watt cool white. The other should be a 40-watt warm white.

8. Begin A Regular Watering Schedule

Now that you have removed the plastic covering, you will need to provide a little water. 

Don’t overdo it.

Just keep a close eye on the growth medium and keep it slightly moist.

9. Transplant Your Little Geraniums Seedlings To Their Own Pots

Once the seedlings develop the first set of true leaves, do these:

  • Repot them into individual containers. Do this by gently steadying the individual plants by holding the leaves lightly.
  • Avoid handling the plants by their stems because this can cause breakage. 
  • Use a spoon or similar implement to gently dig under and around the little plants, one at a time, to lift them from the soil with roots intact.
  • Transfer the seedlings to their prepared, individual pots.
  • Plant them at a depth that places their seed leaves (the thick initial leaves that precede the true leaves) at the soil level. 

10. Adjust The Height Of Your Fluorescent Lights 

At this point, adjust your fluorescent lighting as needed to accommodate the added height of the young geranium seedling plants and their containers.

Remember that the lights need to be about six inches above the plants. 

11. Provide Lower Nighttime Temperatures

You will also need to adjust the temperature.

Your young plants will do best at temperatures of 70° to 75° degrees Fahrenheit during the day and 60° to 65° overnight. 

12. Begin Watering Your Little Plants Just As You Would Grown Plants 

Wait for the surface of the soil to dry and then water thoroughly.

Remember that geraniums (and most plants) need containers with good drainage, light, well-draining soil and should never stand in water. 

13. Fertilize In The Early Spring

You should not need to fertilize your young geraniums until you place them outside for the springtime.

When using a good quality potting mix (especially one that has slow-release fertilizer included), young plants will get all the required nourishment needed from the soil. 

Once outdoors, give them a little boost of a diluted, water-soluble fertilizer to get them started in their new environment.

Repeat this application once every couple of weeks throughout the spring and summer. 

14. Transition Young Plants To Their Outdoor Setting

When spring comes, don’t just plop your little plants outdoors.

This undoes the hard work as the plants will die of shock.

Instead, take care to acclimate them a bit for a couple of weeks. 

Begin by placing them in a sheltered outdoor area in the shade.

Then, move them gradually into a sunnier area.

If you tend to get very cold nights in the springtime, you may even want to toss a light sheet over your plants overnight to protect them initially. 

After several weeks pass and all danger of frost has passed, you can plant your geraniums into the landscape or planters in settings that receive partial to full, bright, direct sunlight.