Penstemon confertus aka Lesser Yellow Beardtongue

Penstemon confertus is a small plant that lives for years. It belongs to the Plantaginaceae family. Its common names are yellow penstemon and whorled penstemon. Its native range spans Alaska and the northwestern United States. It also grows in western Canada, including Alberta and British Columbia. Wild plants grow in meadows, by streams, and in open woods. They range from low ground to foothills and mountain sites. Some grow in dry, sandy pinewoods too.

This plant forms a small, upright clump. In gardens, it grows about 0.3–1.6 feet [0.1–0.5 metres] tall and wide. It takes two to five years to reach full size. Its green leaves have a lance shape. The plant sheds them as part of its yearly cycle. Dense flower spikes rise above the leaves from April to June. Each small, pale yellow bloom has a tube shape. Its mouth flares out. The blooms crowd each spike and give it a full look.

Grow it in rich soil that holds moisture but drains well. It likes full sun but accepts some shade. Chalk, loam, or sand can suit it across a broad pH range. It does best in moist spots, such as stream edges and woodland gardens. It can cope with drier soil where the site stays cool. Sources give quite different guides to the cold it can bear. The RHS gives H3, for mild or coastal British sites. Plants For A Future lists USDA zones 3–7. The RHS says to use dry mulch in cold areas for winter protection.

Its small size suits beds, borders, and informal cottage gardens. The RHS also lists gardens for wildlife, courtyards, and coastal sites. Cut off spent blooms to help it flower longer and stay strong. Cut stems to 0.5 feet [0.15 metres] in late winter or early spring. Split plants in spring, or take cuttings in summer. Disease is rarely a major problem. Mildew and grey mould can still occur. Slugs, snails, and aphids may attack it. Leaf and bud eelworms may attack it too.

Plants For A Future notes a drink made from dried leaves and stems. Strong brews can act as a laxative, so food use has limits. That source lists no other known hazards. It notes past use of roots and outer bark for gut complaints. People also used prepared leaves and stems to dress wounds. These past uses do not prove that such treatments are safe. Boiled flowers have also yielded a blue dye that lasts.