How to Plant, Grow, and Care for Pineleaf Penstemon

Pineleaf penstemon, Penstemon pinifolius, is an evergreen perennial native to New Mexico and Arizona. It differs from other cultivars of penstemon as it has needle-like leaves but flowers similar in appearance to other varieties. 

In their native habitat, they are known to thrive in hot, dry climates in areas with rocky soils. They are low-maintenance and drought-tolerant once established. This makes them a wonderful addition to your rock garden, especially along garden borders. 

Brightly colored flowers that are tubular in shape are said to be the best flowers for attracting hummingbirds. For this reason, the pineleaf penstemon and its nectar-rich tubular-shaped flowers are known to be a magnet to hummingbirds and other pollinators like butterflies. 

Given the ideal growing conditions (like that of their native New Mexico and Arizona), they will flower profusely throughout the growing season beginning in early spring. Not only can they be added directly to the landscape, but they are also suitable for containers and small space gardens. 

If you’re looking to add a low-maintenance, pollinator-supporting, low-water-use variety to your xeriscape landscape, then look no further than pineleaf penstemon!

Its unique foliage and bright orange flowers will bloom and add interest to your garden all summer long. On a sunny day, the flowers will be visited by bees and butterflies often, and your local habitat will thank you! 

What is Pineleaf Penstemon?

Pineleaf penstemon, known botanically as Penstemon pinifolius, is also sometimes referred to as Pineleaf pinifolius, pineleaf beardtongue, pine needle beardtongue, or beardtongues.

The flowers are similar in appearance to those of foxgloves, and they are sometimes mistakenly identified as such. They also share some common names, like beardtongue. 

Native Area

Penstemon pinifolius has a native habitat in Arizona and western New Mexico, where it grows on rocky outcrops and forested mountains. It is native to areas it has adapted to hot, dry climates. It looks awesome alongside English lavender and native grasses, for instance. It’s hardy in USDA zones 4 through 10, which extends far beyond its native range.

Characteristics

This evergreen perennial showcases dark green foliage with needle-like leaves along the stems. The flowers bloom from early spring through summer and into late fall (May through October) in most areas.

Because it grows in rocky soil, it’s a perfect plant for rock gardens and xeriscape gardens with a rocky soil type.

Varieties

There are many different types of pineleaf penstemon, but there are a few popular types that are worth mentioning. They are all native to the same areas the main cultivar is from and thrive in USDA zones 4 through 10.

There is a dwarf variety called Penstemon pinifolius ‘Luminous’ that has a more compact and bushy growth habit and bright orange-yellow flowers. 

The cultivar Penstemon pinifolius ‘Wisely Flame’ has received the Royal Horticultural Society’s Award of Garden Merit. Its bright orange-red flowers sit atop needle-like foliage resembling small flames. 

Penstemon pinifolius ‘Mersea Yellow’ is one of the few truly yellow penstemon cultivars with lemon-yellow flowers. 

Planting

To grow pineleaf penstemon, choose a well-draining location with full sun. Prepare the soil by loosening it to a depth of six to eight inches and mixing in some coarse sand or gravel to enhance drainage, as it prefers drier conditions.

Space each one about 12-18 inches apart. Dig a hole slightly larger than the root ball, typically about four to six inches deep, depending on its size. Place in the hole so the crown is level with the soil surface, backfill gently, and tamp down lightly. Water thoroughly after planting, but avoid overwatering, as it is drought-tolerant once established.

Mulching with small rocks or gravel can help retain soil moisture and mimic its natural habitat.

How to Grow

The beautiful flowers and attraction of pollinators to your garden are reason enough to grow pineleaf penstemon. Adding to that the fact that it is equally low-maintenance and drought-tolerant, what’s not to love? 

Light

Pineleaf penstemons do best in full sun and need at least six to eight hours of direct sunlight per day. The fact that they originated in places like New Mexico and Arizona means they can successfully be grown in hot and dry locations with plenty of full sun. 

Choose a sunny spot in your garden and keep in mind that it grows stems that reach 12 inches tall, so be mindful of not shading out smaller specimens. Pineleaf penstemon can survive winter and late spring frosts as well as the heat of early summer.

Water

While your pineleaf penstemon is getting established in your garden, water it regularly. After a few weeks, it will have adapted to its new climate, and you can begin to back off on watering.

Additionally, as the years pass, your pineleaf penstemon will need less and less water as well. These are, after all, drought-tolerant types that love hot and dry weather. 

During their first season, water at least twice weekly. In their second year of growth, cut watering in half. By their third year, they can be watered once every one to two weeks or not at all if your garden receives enough rainfall to meet this requirement in your area. 

If you’re unsure as to whether or not your pineleaf penstemon needs to be watered, then just stick your finger into the soil near the base. If you can feel some moisture, then it’s not time to water again yet! However, if the soil feels dry, then it’s probably time to give it a drink. 

During the winter, you can stop watering altogether, as any snowfall will provide all the moisture they require.

You can, however, water your Penstemon pinifolius in the winter if there is no snow on the ground currently, no snow in the forecast, and air temperatures are above 40°F (4°C). Otherwise, watering will not be necessary.

Soil

Pineleaf penstemon is an adaptable native that does not necessarily have a preferred soil type. It can survive a wide range of soils, from clay to loamy and even salty soil. Its main requirement when it comes to soil is that the soil has excellent drainage. It does not like to be in standing water or excess moisture. Rock gardens are a great place.

Penstemon grows best when the soil is able to dry out between waterings. If you need to increase the drainage of your soil, you can amend the planting site with perlite or even some sand.

Or if you’d like to bypass amending the garden soil altogether, then you can also easily grow pineleaf penstemon in containers utilizing a cactus potting mix (which has been made to have excellent drainage!).  

Temperature

They do not require any additional protection or cover over winter, especially in the USDA zones where they are hardy. Although some of the evergreen foliage may die back, the slender stems of these will come back to the garden in the early or late spring, so long as their roots are able to survive.

Fertilizing

Adding to the list of reasons why pineleaf penstemon is a wonderful low-maintenance addition to rock gardens is the fact that fertilizing is not necessary.

They actually prefers lean soil. The addition of fertilizers or even top dressing with compost can do more harm than good. 

Over fertilized penstemon can grow stems that are too tall too quickly and can become lanky and flop over under their own weight. For this reason, there is no need to amend the planting site with compost or fertilizers at transplant time.

Maintenance

Pineleaf penstemon does not require much maintenance and can be left to grow wild. However, a few pruning and repotting tips will benefit them and make them look good throughout the season.

Pruning

Pineleaf penstemon benefits from pruning throughout the growing season to encourage another bloom period. The best time for deadheading spent flowers is generally beginning in late spring and into midsummer (June to August). Remove spent flowers a few inches below the blooms. This will encourage your penstemon to continue blooming into late fall and up until the first frost.

As the growing season comes to an end, it is prudent to prune back to a height of about six inches. This will help prepare it for the winter months and ensure bushier growth come late spring. 

Pineleaf penstemon does not spread aggressively or become invasive even in its native range and USDA zones where it’s hardy. It can spread via self-seeding. If you’d like it to spread in this way, then leave the last blooms of the season standing on their stems in order to go to seed. 

Once the flowers have died back and the seed pods have dried, then you can collect them for planting in the spring or you can break them open and let the seeds fall where they may. The second approach mimics what they would do naturally in their native range without human intervention. 

Repotting

When grown in a container, pineleaf penstemon can benefit from being repotted. Since this penstemon is a short-lived perennial, repotting can be avoided by planting it in a container that is the size of the fully grown penstemon in the first place.

There are some challenges with this method, however, since a bigger pot means you’ll need to water it more often (more soil means more space for water to run off and away from the roots). 

If you’ve found that your penstemon is outgrowing its current container, then you may need to choose a suitable pot that is a few inches larger than its current vessel. Choose a pot that will be as wide as you expect your penstemon to have grown by the end of the season. 

This can be repeated each year, with pots increasing in width until it is fully grown. After you dig it up and re-pot it, then it will need to be watered regularly for the next few weeks until it has settled into its new home. 

Propagation

As mentioned above, the evergreen native pineleaf penstemon can be propagated most readily by seeds. However, if you’d like to give your penstemon propagation a head start, then they can also be propagated by softwood cuttings taken from stems in the early summer. 

Be sure to take the young and flexible softwood stems and not the old wood at the base. Remove the evergreen foliage from the bottom few inches of the cutting, dip it in rooting hormone, and then place it into a pot with well-drained soil.

In a few weeks, the cutting will begin to grow roots and become established. Then it will be ready to transplant into its permanent home. 

You can also divide your penstemon in either the spring or fall. Fall division gives it a chance to establish over winter rather than competing with the harsh heat of the summer during this delicate phase.

Dig up your penstemon and cut through the root mass, splitting one perennial into two. Replant both in a sunny spot, allowing for appropriate spacing between them.  

Common Problems

Pineleaf penstemon is as trouble-free as it gets when it comes to low-maintenance natives. There are, however, some problems to be aware of. 

Growing Problems

Too much water and organic matter in the soil can have adverse effects causing them to grow tall, lanky, and begin to flop over. If this occurs they might need additional support like a stake. 

To avoid this and keep them sturdy and upright, make sure to allow the soil to dry out between waterings, and grow in an area with excellent drainage, like rock gardens.

Avoid low-lying areas in your garden or areas close to a downspout. Adding organic matter to the soil also helps with moisture retention, but this is one that prefers the soil to be able to dry out. 

Pests

Another benefit of growing pine leaf penstemon is that it is free of serious pest issues and is even deer and rabbit-resistant!

Diseases

In addition to being pest-resistant, there are also no serious disease issues.

Frequently Asked Questions