These Persicaria tinctoria plants were harvested in the first week of September.

The seedlings were planted in the last week of December the prior year. This is an unusual timeframe. The seedlings were germinated in Los Angeles and allowed to grow to semi-maturity. By mid May, the plants were about 18" tall and had split into more than 20 stems. At this point the tops of the stems, about 6-8" lengths, were clipped between nodes and gathered. The lower leaves of those gathered stems were stripped off, leaving only few small leaves and the bud tip growing. These stems were placed in water, out of direct sunlight, for one week following the information given here :
http://www.grahamkeegan.com/blog/propagating-indigo-plants-from-cuttings
Dozens of adventitious roots quickly began to grow from the lower nodes of these stems, reaching a length of a few inches after seven days. These small clones were unceremoniously squished into plastic bags with damp paper towels for the roots and flown to Vermont (where the author has more room to grow than in Los Angeles) and transplanted into the ground. The plants were placed into well draining, fertile soil on the first of June, spaced approximately 10-12" apart, watered once and left to fend for themselves. By transplanting rooted clippings, effectively, 4 plants were turned into 120. Despite the journey and forced transplant there was 0 plant loss.

By the first of September, the plants had grown to maturity.
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The full grown leaves measured between 6 and 8" long from the point they naturally snap off the stem. The color was a deep rich green.
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The mature stems in the center of the patch reached approximately 30-36" in height. The outer stems were equal in length but did not stand straight up, instead, bowing toward the outside.
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The plants had reached an average of setting 19 leaves per stem with no sign of flower buds, despite being 8 months old. Cloned plants from the same set in Los Angeles began to set seeds in June after the 14th node. Perhaps the change to a cooler, wetter climate climate set back their reproductive cycle.

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Approximately 15 plants were harvested for an experiment with a fresh leaf vat. The bottom 12" of stem were left to allow for regrowth of the plant for a potential second harvest. About 7lbs of stems and leaves were crammed into a 30 quart stock pot.
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