Moonshine yarrow can be a low maintenance perennial or higher maintenance, depending on how one chooses to maintain it. Usually, flowers are allowed to fade and dry on the plant, creating an attractive contrast between new, active, and dried flowers. Some people prefer to dead head (cut off) fading blooms. This is best done by cutting off most of the stem attached to the flower (either entirely or down to where there are small leaves). This will extend the bloom cycle, but because Moonshine yarrow is a prolific bloomer, it also creates much more work in the garden. The plant does not care either way. Cutting back the whole plant hard (down to just above the lowest leaf buds, or no taller than a couple inches from the soil level) as soon as flowering is complete and stems are looking ragged will stimulate new growth, the next round of flowering, and maintain a tidier appearance (S). Every few years, especially if plants have begun to loose vigor, divide them. In very early spring, cut them into chunks with a sharp spade and dig the chunks (divisions) out. Only replant divisions that have vigorous looking root systems, usually from the outer areas of the clump. Depending on the age of the plant, or time since last division, the inside part might be woody, with few healthy roots. These parts should be discarded, or removed from the healthier parts and discarded, as you will still have more plants than you started with. Extra plants that you do not need in the garden can be put in a pot with potting soil, grown out until their roots form a new healthy root ball, and planted in new gardens. Divisions directly and newly planted in the garden need to be treated like newly planted plants, with regular water and extra attention (S).
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