How To Grow French Geraniums, Pelargonium Grandiflorum

Not all geraniums are created equal, friends, though honestly geraniums are wonderful, so please don’t ever consider being a geranium snob, as I may have been once upon a time. I just picked up this very bright pink french geranium (as we call them in Israel) though it goes by the name of pelargonium grandiflora anywhere, so refer to it by that to get this exact plant!

Who can resist this lovliness? And of course, geraniums are so simple to propogate from stem cuttings, so from this one plant hopefully I’ll have a few more next year!

Pelargonium grandiflorum (commonly known as the Regal Pelargonium, Martha Washington geranium, or English geranium) is prized for its large, ruffled, two-toned spring blooms. Unlike common zonal geraniums, they prefer cooler spring weather, and actually need a cool period (i.e. not freezing winter, but cold) to bloom.

How To Care For Pelargonium Grandiflorum:

1. Soil and Potting

• Soil Mix: Use a loose, fertile, and well-draining potting mix (e.g., standard potting soil mixed with perlite) with a neutral to slightly alkaline pH.
• Containers: Regal pelargoniums prefer to be slightly root-bound. Choose a pot that is only slightly larger than the root ball and ensure it has drainage holes, as these plants are highly susceptible to root rot.

2. Light and Temperature

• Light: Place in full sun (at least 6 hours daily) to encourage vivid flowering. However, provide some light shade during intense, sweltering summer afternoons.
• Temperature: They thrive in moderate, frost-free climates. They do not handle hard freezes; protect them if temperatures drop below 7°C (45°F).

3. Watering

• Soak and Dry: Water moderately when the top inch of the soil feels completely dry.
• Avoid Soggy Roots: Never let the plant sit in water. Always water the soil directly, not the foliage or flowers, to prevent fungal diseases.

4. Feeding

• Fertilization: They are lighter feeders than zonal geraniums. Apply a balanced liquid fertilizer (such as 10-10-10 or 20-20-20) every 3 to 4 weeks during the active growing season.
• Avoid over-fertilizing, as excess nitrogen will produce an abundance of leaves at the expense of blooms.

5. Pruning and Deadheading

• Deadheading: Regularly pinch or snap off spent flower stalks near the main stem to prompt continuous blooming.
• Pruning: Prune the plant back to about 10 cm (4 inches) after the blooming period ends to maintain a bushy, compact shape.

6. Winter Care and Forcing Blooms

• Overwintering: Before the first autumn frost, bring potted plants indoors or move them into a frost-free, bright location. Cut back watering significantly during the winter months.
• Initiating Blooms: To get spectacular blooms in the spring, the plant must experience a “chilling” period of about 6 weeks during winter (kept in a bright, cool room around 10°C / 50°F).

Okay, got it? For my zone/weather conditions I can leave this geranium outdoors for most of the winter, but will likely keep this in a pot that can be brought indoors if temps drop below 7C……then of course I will be sure to put it back outdoors for the mandatory cold period of 6 weeks, as bring on the blooms!

Also, important to note that the plant prefers to be slightly rootbound, so you are not doing it a favor by potting it in a great big pot thinking it will be happy with room to grow. Looks-wise you can always place a smaller pot within a larger pot for a more proportionate look, setting the inner pot on top of something.

Okay, happy geranium raising!