1 litre sized pot.  Heliopsis helianthoides Summer Nights is a herbaceous perennial.  Bronze tinted green foliage emerges in spring.  The golden bright yellow flowers that follow are borne on strong stems and have a mahogany-red centre.  Dead heading helps extend the flowering season.  Likes full sun or part shade in well drained, moist soil.  Flowers reaching up to 70-90cm tall and loved by bees and beneficial insects.