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In My Garden Blog

November 20, 2008
Western Mountains and High Plains
By John Cretti,
Denver, CO

2952
My ivy geranium is loaded with blossoms in the sunny south exposure with cool nights.

Growing Geraniums Year-Round

Now that killing frosts have brought the outdoor gardening season to an end, it's fun to reward yourself by growing some annuals indoors. Luckily, I was able to save a few of my favorite geraniums, and just a few weeks after placing them in a sunny, south-facing room, the ivy geranium is beginning to put on another colorful show.

Here are some simple techniques to growing and coaxing geraniums to bloom indoors. Whether it's the common geranium (Pelargonium x hortorum) or ivy-leafed geranium (P. peltatum), be sure to have them potted in a well-drained growing medium. I like to use potting mixtures that have a good supply of organic matter such as screened compost and sphagnum peat moss. If you make your own you can combine equal parts of garden loam, peat moss, and coarse sand or perlite.

Once indoors geraniums will have different watering needs than when they were growing in the outdoor garden. It is important to check them daily to make sure they are receiving enough moisture. Indoor temperatures can vary greatly, and forced-air heating dries the air which in turn dries out the plants. My best luck has been to water thoroughly, then let the potting mixture dry out slightly between waterings. Rather than watering when the soil surface dries, which could lead to overwatering, check the moisture level of the potting mix to a depth of 4 inches to determine when the plant needs watering. Then, apply enough water so that some drains from the bottom of the container.

With the day length shorter than in summer months, be careful about feeding your indoor geraniums. More often than not, we tend to apply fertilizer too often indoors. If your geranium plants are growing in bright light conditions like mine, fertilize every three weeks with a diluted high-phosphorous, soluble plant food. In lower light intensities, apply once a month. Apply fertilizer according to the directions on the label, and make sure that the potting soil is moist before feeding.

The trick to get geraniums to set flower buds and bloom indoors involves the lighting conditions. My best luck has been in the south-facing, full-glass sliding door. My ivy and old-fashioned geraniums are within a few feet from the bright winter sunlight that enters the room when the curtains are opened. Of course they will often grow and bend toward the window, but I keep them growing more evenly by rotating the containers a couple times a week. In this south-facing room the leaf color is good and the stem growth and bud development are healthy and vigorous.

If you don't have as bright a location as mine, satisfactory results can be obtained at other exposures if the plants are placed on windowsills to maximize light quality. Artificial light from cool fluorescent bulbs (40 watts) placed a foot above the plants for 14 to 16 hours can be utilized, too.

The ideal temperatures for geraniums indoors are warm days and cool nights. My south-facing room generally gets between 60 to 65 degrees during the day, but since it is not heated, the temperature gets down to 45 to 50 degrees at night. It is best to avoid locations where the plants are exposed to cold, hot, or drafty areas.

So go ahead and enjoy the ever-dependable, old-fashioned or ivy-leafed geranium in your home. It's a tradition passed down from my Italian grandmother and relatives and I've always made the effort to enjoy the colors and scents of this wonderful annual.

add a comment Comments on Growing Geraniums Year-Round

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Tanya
Kudos to you for not giving the usual advice of putting in the dark
forcing them into some suspended animation and bringing out in the
spring.  Way too much work and why waste those wonderful flowers
that could have been over the winter. ;)

My mom always has geraniums indoors in the winter.  Many a
Thanksgiving was spent dodging the plants set up in the window.  Now
the cats have to fight them for windows. :)

Tanya sitting here surrounded by her geraniums at work.  
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Jan
I have saved geraniums yearly. Your comments regarding watering and
light will be helpful for me. I wanted to know whether I should have
cut down my geraniums when I brought them in. I hosed them, cleaned
them up, and just pulled off the obviously weak stems. Should I cut
them down now,and if so, how much should I leave?
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Kellie
My geraniums won first place in the fair this year because I brought
them in last year. I cleaned them well in the spring, kept them fed
and rotated regularly. I put them outside in June and feed them
often with super bloom. The plant was two feet high and covered in
buds and blooms all the way around. 
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