Geraniums are fun to grow from cuttings, and the best time to take them is late August and early September. Rooting cuttings and growing them into garden-center style geranium transplants is not only exciting, but it saves money. Several years ago, Mary and I bought 8 geranium plants which we grew in planters during the summer. That fall we took cuttings of them, getting about 12 cuttings per plant, which yielded 96 geraniums. The following fall we took multiple cuttings from the 96 geraniums. So in a 2-year timespan we turned 8 geraniums into several hundreds.
- Recycled plastic greenhouse cell-packs or other small pots. Sterilize containers by soaking in a solution made of one part bleach in ten parts water. Rinse in plain water to remove bleach residue. Good sanitation will reduce the chance of cuttings rotting before rooting.
- Several mixtures can be used for the rooting media: Well-drained potting soil composed mainly of peatmoss and perlite will work, but the mixture with which I’ve had greatest success is made of equal parts peatmoss and sand. Mix well and moisten before using.
- Although it’s possible to root geraniums in water, they rot more easily and produce weaker roots.
Taking the Cuttings:
- Depending on the size of the mother plant, a geranium grown outdoors all summer can yield from ten to twenty cuttings.
- The ideal cutting is about three inches long, taken from the tips of geranium branches.
- Snap the cuttings off by hand right below a leaf joint, called a node. Knives or shears can spread rotting organisms across the cut surface, so hand-snapping is preferred.
- Remove any blossoms and flower buds from the cutting.
- Snap off leaves from the lower portion, leaving only the top two or three leaves.
- Some gardeners prefer to let the cuttings sit for two to eight hours to let the cut surface heal. If you do, sprinkle with water lightly to avoid excess wilting.
Procedure for rooting:
- Fill sterilized cell-packs with pre-moistened peatmoss/sand mixture.
- “Stick” the cuttings by making a pencil hole in the media, insert the cutting, and gently firm media around the cutting’s base so it doesn’t wiggle. Insert only about an inch of the cutting into the media.
- It’s best not to use rooting hormone powders with geranium cuttings, although they can be helpful in rooting other types of plants. Geranium tissue can be damaged by the products.
- Water cuttings gently after sticking with a fine-droplet sprinkler until media is thoroughly wetted.
- The natural atmosphere outdoors in late August and early September is very favorable for rooting geranium cuttings.
- A perfect location is close to the house in a wind-protected spot receiving a filtered mix of shade with just a little sun. Full sun is usually too intense for cuttings.
Care of Cuttings:
- The most difficult part of the process is developing a feel for proper watering of the cuttings.
- If geranium cuttings are kept continually soggy, they easily rot.
- Watering frequency depends on location, but cuttings often require a light sprinkling every other day.
- Watch the media as it goes from dark and moist to light and dry. Let the surface dry a bit between light sprinklings. Avoid heavy watering that overly-saturates media.
- It’s much better to err on the dry side with geranium cuttings, if in doubt about watering. Rot from soggy media is more common than failure from under watering.
- Remove all flower buds that might arise during the rooting process.
Checking for rooting:
- It takes two to three weeks for rooting to begin.
- Avoid the temptation to pull up on cuttings to see what’s happening, which can tear newly-forming roots.
- To satisfy curiosity, use a pencil to gently lift the cutting out of the media, inspect and then replant immediately.
- When new leaf growth begins at the cutting’s tip, it’s a sign it’s well-rooted, which usually takes at least four weeks from the time cuttings were taken.
Potting new plants:
- When cuttings are well-rooted, they’re ready to pot up.
- Use a high-quality mix like Miracle Gro potting mix. Moisten well before use.
- Pot diameter shouldn’t exceed four to six inches. New cuttings potted in too-large pots will be overwhelmed. Geraniums like to become “potbound” before moving into the next larger-size pot.
Growing new geraniums:
- Move newly potted geraniums indoors to a sunny window. During winter’s short days and low-angled sun, a southern exposure is best. East or west windows can work also.
- Geraniums grow beautifully all winter under fluorescent lights.
- By next spring, geraniums will be ready for outdoor pots, planters and flowerbeds.