January 24, 2010

Mastering Regal Geraniums

A shot of some Pelargoniums from the front sand bed in the greenhouse from last May. These we're still young, but now the plants are getting larger, and need some care so that a better display can be had. This means cutting back, taking cutting for young plants that will bloom next year, and ordering many more new cultivars and species. Something to do on a January weekend.

A scented Pelargonium of the Apple persuasion, awaiting a hair cut. Cutting will be taken.

Trimmed back, this Regal Geranium will be fertilized and encouraged to grow on in the cold greenhouse, where it will set bud and bloom in late spring and early summer, as the days grow longer.

A dip into rooting gel, and then into the tray of cuttings. I had so many, that I was able to edit out only the strongest cuttings. With more cultivars on the way from Geraniaceae.com, I will need room!
or even July.
Regal Pelargoniums, or Pansy Faced types, awaiting to be placed into a propagation tray to root.
A tray of Pelargonium cuttings, ready to be placed in a protected area in the back of the greenhouse, on the sand bed to root.
Regal Pelargoniums, or more commonly known as Regal Geraniums or Martha Washington Geraniums have a long history as a flowering pot plant in both North America and Europe, but they also have a strong following with greenhouse enthusiasts who look forward to their blast of flouncy flowers in May and June. Other crosses which are similar in floral shape, are the Pansy Faced varieties, which also have a large, fancy flower. Regal Geraniums are not true Geraniums, but most of you all know that, they are Pelargoniums, but hybrids with a showy, large flower head, and they require a unique treatment compared to other Pelargoniums, for we grow many types and species, ranging from the summer dormant geophytic species all the way up to the common red geranium. But Regals require regal treatment, for they take longer to come into flower than the zonal type of pelargonium (the ones that people usually call geraniums). Commercial growers have to worry about all sorts of things ranging from the perfect fertilizer at the perfect time, and artificial lights ranging from 14 hours to 18 hours of daylight, so most just buy pre-bud-initiated liners ( rooted cuttings with buds) and then pot them on.

As a home grower we can relax a bit, but this is because we have a cool greenhouse. Indoors, keeping Martha Washington Geraniums is more challenging, since they require a long, cold winter period blow 65 deg. in the day, and around 50 at night. So combined with their complex photoperiod, and their need for cool temps, you can see why they are difficult as house plants, but dumb easy in a greenhouse. If you have an old house, with an unheated sunny room, or a sunporch, or a cold window, they might be easier, but if you live in an apartment or a modern home, getting them to bloom will be as easy as getting any other old fashioned house plant into bloom like a Clivia, virtually impossible.

Regal's have a 'season' and once you start thinking of them as to get them into bloom, for they require a fourteen hour daylight period in to order to form buds. In commercial greenhouses, they are grown much like other day length sensitive plants like Pointsetia and Christmas Cactus, but without artificial light to lengthen daylight period, they tend to bloom in June

The large, flowering Regals one sees in May for Mothers Day are grown on a biannual basis, where it takes two years to get a decent sized plant. But I have both larger stock plants, and smaller 3 inch pots. Both require cutting back while they are in their slowest period of growth, which is now, during October to March. I am taking about a dozen cuttings of each cultivar, and plan to plant about 3 to 5 cuttings per pot. A simple dip in rooting hormone ( I know, I should have removed some rather than dip the cutting in the container, but it's my greenhouse and I am lazy!). These cuttings should root within a few weeks, for these Pelargoniums root fast in the cool nights and warm days in the greenhouse.

The mom plants were repotted with fresh soil, and fertilized with a weak solution to get them started. The are all now moved to the upper shelf into full sun, and soon growth will begin. If you are looking for some interesting Geraniums or Pelargoniums, then try some of these sources in the US. Geraniaceae.com, and in the UK< try Gosbrook Pelargonium Nursery ( why don't I live in the UK? WIll someone find me a job there?).


  1. Yikes, you must be getting tight on space on the greenhouse with all the cuttings you are doing this month.

    What an interesting project for this time of year.

  2. great post! I don't bother with Geraniums as we don't have a basement, but maybe I can figure something out in our hoophouse.

  3. Ohmigosh, hats off to you, that looks like a lot of work!

  4. Anonymous7:31 PM

    Isn't propagation of these plants illegal?

  5. Love this tutorial! I'm using it today on my blog (hope you don't mind). Of course, I've credited you and linked back. Thanks for the great info.

  6. Anonymous8:44 AM

    I have never had any problems growing these as they are brought in before frosts to an unheated lean-to greenhouse, I take as many cuttings 2" as I can at this time and again in spring I don't even use rooting compounds and they grow fine.
    However just want to know if they would also grow in peat?

  7. Can martha washington geranium grow with jasmine in one pot?

  8. Can a Martha Washington geranium and jasmine climbing shrub be together in one pot?

  9. I have no problem with my regals growing, I just can't get them to flower. May be I am in wrong place in Australia to have them flower as I am in sub tropical. Bought them on line because they were gorgeous and thought they would be just like the Zonal Geraniums to grow. :(


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