Caring for Ageratum

Ageratum - While most folks plant this popular annual as a bedding plant, it works very well in a hanging basket or window box. Food for thought while the snow is still falling.

Ageratum - If you are thinking of adding some more Ageratum to your garden bed, here are two new introductions to research.
New in 2002 - Ageratum 'Leilani Blue' grows to a 14-16 inch height and shows large clusters of blue flowers
New in 2004 - Ageratum 'Alto Blue'

Ageratum - Ageratum can be started from seed indoors. Start them 6 - 8 weeks before all danger of frost has passed. Don’t cover the seeds; they need light to germinate.

Ageratum – Plant Ageratum seedlings purchased at the garden center or nursery as soon as danger of frost is past and the soil is warm (when night time temperatures stay above 50 degrees). Depending on where you live this may be as early as April or as late as June. Ageratum prefers full sun but can handle part shade. The soil should be fertile, moist and well drained. Space plants 6 to 8 inches apart depending on expected height of the variety you are planting. To avoid fungal disease problems, be sure to plant Ageratum in a location with good air circulation to help prevent fungal diseases such as powdery mildew.
Container design idea from Proven Winners for spring to early summer - In a medium to large container combine two each of Ageratum 'Artist Purple', Licorice Plant 'Petite Licorice', and Petunia 'Supertunia Priscilla.

Ageratum - Ageratums do not want a lot of fertilizer, especially if they are growing in good soil containing lots of organic material. In that case, they want only a light feeding in the spring when the seedlings are set out, about a half a tablespoon of slow-release granular fertilizer per plant. In poor soils use a bit more; one tablespoon of slow-release granular fertilizer per plant. That is all you need for the season.

Optional task – Ageratums grow best when mulched. As soon as the Ageratum seedlings are tall enough, spread a 2 or 3 inch layer of some organic material such as chopped leaves, dried grass or wood chips on the soil around the plants.

Ageratum – This plant does not like to have its soil dry out; a moisture-retaining mulch will cut down on how frequently you have to water it.
We don't know exactly why this happens, but those pretty blue blossoms of Ageratum will usally turn up as pink on any photos that you take; go figure.

Ageratum – Unlike many flowers in the garden, Ageratum are perfectly happy to be transplanted to a new spot when they are in full blossom. Some people keep a row of Ageratums tucked away in the vegetable garden so when holes appear in the flower bed, Ageratum is standing ready to fill in with full blue color. Best to do this on a cloudy day and water the plant very well.
Optional – Cut off old flower clusters as they brown to keep the plants looking better and blooming more. If you have a lot of brown clusters, shear the plants back about one third and you will have more blossoms in about two weeks.

Ageratum – Interesting fact – The genus name, Ageratum, is derived from Greek and means ‘without age’, a reference to the long-lasting flowers.

Ageratum - Continuing to deadhead spent blossoms keeps this plant looking good right up to first frost.

Ageratum – After the first hard frost your Ageratums will have died and can be removed to the compost pile.

Ageratum - This common annual is often called Floss Flower or Blue Fleece Flower just to keep us all confused.

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