Because geraniums do not have “resting structures” like bulbs or tubers, they should be brought in for the winter. Three frosts is enough to kill them. Leaving the stalks on, dig them, pot them or clump them together and wrap them in a tarp, and put them in a cool (not freezing), dry area. Come spring, cut them back, move them back into the garden, and begin watering. Note: If they freeze during the winter, they will not come back.

Interesting problem to have, Ethan. The heavy light may be contributing to the growth; so, too, water. It’s actually normal for geraniums to get bushy. Try this: Prune out all old or unhealthy stems (if you have any!). Pinch back (pinch out) new growth, once it reaches a few inches. Pinch it to ½ to 1 inch from the tip. You can also prune about a third of the plant and not suffer loss. And check the pot size; sometimes rootbound plants “force” their growth to the top. BTW, you can do this and still trans-fer/-plant the geranium outdoors for the summer. Lucky you!

You can use a water-soluble 20-20-20 fertilizer. Mix 1 teaspoon into 1 gallon of water. It’s also important to pinch off the faded flowers and longer stems to keep the plant bushy and healthy. You can easily propagate your plants buy putting the stem cuttings into moist vermiculite or any well-drained sterile soil mix. Put a plastic bag over the top and in a week or so the cutting will have roots and you can plant it in a bigger pot.

Hi, Janice: This just wouldn't be practical, as it takes a lot of light and warmth to keep geraniums going. Please see the answer to Vika below -- and thanks for asking!

Hi Vika,
The geraniums need a lot of light and temperatures between 65 to 70 F to do well as houseplants. Another way to overwinter geraniums is to let them go dormant by removing them from the pot and hanging them upside down in a cool, dark basement. In the spring place them in pots and put them in a warm sunny spot. Water and they should start growing new leaves soon.

Hi Susan,

You can supplement sunlight with a fluorescent tube light about 10 to 12 inches above the plants.

Hi Frank,
Place the cuttings in a warm location, 65-70 degrees F is fine, with bright, but indirect sun.

If the geraniums are in pots, bring them inside well before frost. Put in a sunny window (south- or west-facing) and make sure the temperatures are about 65 degrees F during the day and 55 degrees at night. Keep the plants humidified. Water when soil is dry (about once a week) and cut them back when they grow long shoots. Fertilize in mid-spring and put pots back outside once you are confident that the last frost has passed.

It could just be age. As the plant grows, the stem must get stronger to support the additional weight of the plant. It is also possible that your plant has a bacterial disease. Check out this extension service page for more information: http://extension.psu.edu/pests...

According to the ASPCA, common or zonal geraniums (Pelargonium spp.) are toxic to cats and dogs. However, other sources say that these plants rarely cause a serious reaction and are usually only mildly toxic. (It might depend on how much the pet ate.) The plants can cause skin irritation (there might be some swelling in and around the mouth), and if ingested, the pet might vomit to get rid of the irritant plant tissue. Depression or lack of appetite might also be symptoms. If you suspect that your pet has eaten the leaves or flowers of geraniums, it's safest to consult with your vet, who knows your pet's overall health condition and issues. Describe to your vet the symptoms and s/he may be able to determine whether the pet should be examined or tell you what signs to watch for and how to keep the pet comfortable.
 
As to true geraniums (Geranium spp.), also called cranesbills or hardy geraniums, we can not find information about their toxicity to pets.

Hi, Mary: It's hard to tell which requires the least care--transplanting to pots, regrowing from cuttings, or letting go dormant--but we suspect the latter is what you want. Carefully dig up your plants now. Carefully shake off any dirt and loose/dead leaves/stems. Remove any sign of mold or other disease. Repeat: Inspect carefully for mold. Place in your (unheated) basement in a way that allows for good air circulation (we put groups in paper bags and hang from the floor joists). Over the winter, they will dry out substantially but hopefully still retain enough moisture to be viable come, say, February. Take a peek every now and then to be sure. (If they seem to be really drying out, accelerate the repotting schedule.) When you're ready to restart in pots, use soil-less mixture and cut back the remaining stems to a point where you can see green life. Water and fertilize lightly but regularly, and replant outside after the projected date of your last frost, which in your area occurs about May 14. Good luck!

In terms of sunlight, is it really bright and direct at least four hours a day? In terms of fertilizer, use a more balanced fertilizer: 15-15-15 or 20-20-20. Finally, you could always repot with new potting soil mixture. Before you do, hold back the watering for 6 to 8 weeks until it's not quite dry and cut it back. After repotting, start watering again, fully moistening the soil, and then allow the top half-inch of soil to dry before watering again. Also, we would try summering your geraniums outdoors if you can.
 

Hi, Ruth, Allow us to introduce you to the geranium budworm, aka tobacco budworm. At maturity, these are moths that lay a single egg at night on the geranium buds. The larvae color may be red or green. These turn into caterpillars that drop into the soil and pupate. As the days grow shorter and seasons transition, the insects "hibernates" in the soil, staying for the winter.
Handpicking is the most common control. Around dusk, look for the worms when you see holes in the leaves or flowers. In daylight they hang around the base of the plant.
If your geraniums are potted, change the soil.
Numerous wasps, bugs  (e.g., Polistes spp. wasps, bigeye bug, damsel bug, minute pirate bugs), and spiders are natural enemies.
We hope this helps.