How much sunlight?

Our goal at Swanson’s is to help you be a successful gardener and enjoy your garden for years to come. We offer a wide selection of plants for all types of sun exposure. Our individual product signs and many plant tags list the optimal growing conditions for these plants in the Puget Sound region. Please feel free to ask any of our staff for more information.

All plants require light to grow. Some plants need lots of sun to carry out the biochemical reactions needed for growth and flowering. Others need very little and may have sensitive leaves which will burn in intense sunlight. The following definitions take into account the amount and intensity of sun typical to the Puget Sound region during our primary growing season (from March to October). 

FULL SUN: a plant that requires “full sun” will grow best in a location receiving direct, unfiltered sun all day, or at least 6 hours of direct sun. Examples: Roses, Lavender, annual Geraniums.
PART SUN: a plant that requires “part sun” needs at least half a day of direct, unfiltered sun, preferably in the hot afternoon (approx. 1 - 4 p.m.). Examples: Peonies, Lilacs, Snapdragons.
PART SHADE: a plant that requires “part shade” needs at least half a day of shade, preferably shaded during the hot afternoon (approx. 1 - 4 p.m.). These plants may also like filtered shade under trees which allow some sunlight to pass through. Examples: Begonias, Fuchsias, many Rhododendrons.
SHADE: a plant that requires “shade” prefers little or no direct sunlight, relying instead on indirect sunlight or early morning/late evening light. Examples: Impatiens, Hostas, Sarcococca.
DEEP SHADE: very few plants tolerate no sunlight at all—those that do are typically dark green and very slow growing. Here’s where you might appreciate Swanson’s wonderful selection of garden art, statuary and decorative stone! Examples: Aucuba, ferns.

“Full sun,” “part sun,” and “part shade” are all terms with somewhat arbitrary definitions. In addition to actual numbers of hours of sun exposure, there are many other factors which can create too much sunlight, not enough, or just right for a specific location. These may include:

  • What time of day the sun exposure occurs
  • What direction the plant is facing
  • Soil moisture and the gardener’s watering habits
  • Presence of nearby structures which may trap heat or reflect light

For example, two plants of the same variety, planted in identical sun exposure may perform quite differently if one location is more moist or dry than the other. Some full sun plants love the hot spot next to a heat-trapping brick wall; others would quickly wilt and prefer to nestle among surrounding plants to buffer the heat. Please check individual signs or tags, or ask one of our staff for specific care requirements.