Bidens aristosa / Bidens polylepis
This is a truly delightful native annual wildflower that flowers in late fall when little else has any color. The massive of bright yellow flowers bring a spark of color to an otherwise dying garden landscape. For this reason alone it is worth adding to the garden flora. Prefers to have more moisture so is best of wetter areas in full sun or partial shade but needs no care once established. Will self seed in ideal conditions and can form large colonies. Deer may eat some but don't seem to bother it that much.
An native fast growing annual it produces slender mid green compound leaves of 3-7 segments arranged in opposite pairs. Each leaflet is slender pointed ellipses with strongly serrated edges. Complete leaves can be as much as 8" long and 4" across in mature plants. The stems are stiff, reddish in color and much branched producing a slender semi bush like plant. Plants can grow from 3' - 5' in height. The flowers are produces at the ends of each stem and are bright yellow, daisy like, each about 2" across and as many as 10 petals with yellow and brown centers. The flowers are slightly fragrant which can become very noticeable in a large colony. The flowers appear in a late fall when little else is often flowering.
Works well in a wet meadow, ditch or in a mass in areas where color is needed in late fall. Ideal for bog garden, and large rain gardens, do not use in small rain gardens as they can overwhelm other smaller plants.
Location and care
Prefers full sun in moist or slightly wet conditions. Ideal for moist ditches runoff areas and rain collection areas. Not recommended for rain gardens and it can take over the whole area with its spreading nature. Prefers richer organic soil, which most often occurs in wet areas anyway. Can be grown in dryer areas provided it is watered, a soaker hose around the roots is idea. However pick a location that gets some shade during the day to compensate for the reduced water. In moist sunny conditions it will easily reseed itself and can create large colonies that can be aggressive if not controlled. However it does produce a really lovely flower display under such conditions. If not desired cut down before seeds fall.
Can be sown in situ after all danger of frost has passed or started in pots in mid to late winter.
Outdoors. Clear area of all weeds and prepare soil, dig in any organic material if the soil does not have a reasonable amount already. Sow seeds thinly and cover lightly. If area is moist enough no additional weeding should be necessary. If a dryer location water daily until the seedlings have established. Thin to about 18-24" apart. Set a soaker hose around the plants roots and allow to run about 1 hour per day at least. No further care should be needed until plants need to be cut down in winter.
Indoors. Sow in mid to late winter. Follow general growing instructions for medium seed.
Excellent cut flower.
Beggar's Ticks, Swamp Marigold's, Bearded Beggarticks
Tickseed Sunflower Flower
Tickseed Sunflower leaf