Raised beds are a fantastic, multidimensional tool for growing both annual and perennial flowering plants. Apart from their aesthetic potential in structured gardens, raised beds are often associated with improved drainage conditions, enriched or amended substrates, the reduced occurrence of weeds, disease, and pests, and optimized plant placement. These may contain just one type of plant or be used for the cultivation of a compatible mix of species – ideally, those that thrive in well-drained soils.
Over a year, raised flower beds may drastically change in appearance. Perennial bloomers offer long-lasting texture and a reliable display of seasonal blooms. Annuals are also fine choices for raised beds, from which their rapid stages of development can be appreciated and well-managed. For a continuous show of flowers, you may combine species, or varieties, that are likely to bloom one after the other. Conversely, you may also group simultaneous bloomers for a single, spectacular burst of color.
1) Ornamental sage (Salvia varieties)
There are hundreds of ornamental sage varieties that are grown for their aromatic leaves and their visual value. Principally used all around the world as a source of compound-rich foliage, sage tends to be perceived as a culinary or medicinal herb. It also brings many benefits to the garden; its seasonal blooms attract hordes of pollinators and are borne on lengthy, eye-catching spikes rising several inches to feet above the mounds of soft leaves.
Ornamental sage plants usually bloom from spring to fall. Some common varieties can tolerate a wide range of ambient conditions and light exposures as long as their roots are exposed to well-draining substrates. As these produce blooms sporting the most vivid of red and blue pigments to the softest of creamy white and pink hues, they are most attractive when they are densely packed into diverse clumps in raised flower beds.
2) Zinnia (Zinnia spp.)
Zinnias are among the most famous flowering annuals due to their vivid flowers and rapid growth rate. The most commonly grown cultivars are usually varieties or hybrids of Z. elegans and Z. angustifolia. These have varied maximum heights; some grow to just 6 inches (15 cm), whereas others may produce meter-long, upright stems with pairs of lance-shaped or linear foliage. For optimal bloom rates, they should be situated in bright light and provided with adequate moisture.
Zinnia blooms are especially attractive when they possess multiple layers of vibrant ray florets surrounding a delicate center of disk florets. Flowers that grow heavy with dozens of petals may have a dome shape. A pack of mixed zinnia seeds would be a great present for anyone cultivating raised flower beds! The seeds should quickly sprout into flowering stems that attract butterflies, bees, and even hummingbirds.
3) Globe amaranth (Gomphrena globosa)
A notable member of the Amaranthaceae family, the globe amaranth is named for its distinctly round inflorescences. These eye-catching features look like textured puffs of vibrant color. The flowerheads actually consist of bracts surrounding less conspicuous, tiny, true flowers. They tend to retain their color even after being dried and incorporated into floral arrangements. Those of some cultivars have a combination of white to deep pink pigments.
Globe amaranth is best appreciated in raised beds as its stems seldom measure more than 2 feet (61 cm) tall. These produce pairs of oppositely arranged, slender leaves with a coverage of fine hairs. As the hairs trap dirt and pollutants, they may look dusty in areas with frequently lifted topsoil. A mulched bed should help keep the leaves free of dirt. Warm, well-draining conditions are necessary for optimal flower production.
4) Lavender (Lavandula spp.)
Raised beds are fantastic for growing Lavandula species, which require good drainage conditions to become well-established and produce their oil-rich foliage and fragrant spikes. Given their wealth of uses in the landscape, some lavender varieties are among the most commonly cultivated herbs throughout the dry and warm regions of their native range. Their stands are suited to the edges of raised beds, where the substrate tends to dry out at a quicker rate.
Sandy loam is the most ideal type of soil for lavender beds as it is free-draining and is likely to retain fewer nutrients than finer mixtures. Drought- and cold-tolerant once well-established, lavender stands can be grown alongside shrubs that fare well in semi-arid climates. Continuous air circulation is crucial to enhancing the quality of the leaves and floral spikes, increasing their resistance to pests and disease.
5) Silver-edged primrose (Primula marginata)
The silver-edged primrose is a fine choice for small plots. This recipient of the RHS Award of Garden Merit is an alpine, evergreen perennial. Its flowering rosettes grow to a maximum height of just 6 inches (15 cm) but can cover a width of about 12 inches (30.5 cm) at maturity. Due to their relatively short full height, they are best situated along the edges of a raised bed, where their late winter to early spring blooms can be appreciated.
Named for the white farina found along the toothed margins of its greyish-green leaves, this primrose is also perfect for raised rock gardens. Ideally, it should be situated in an area that is protected from strong rain as its farina may be washed off. This means that watering should be done in a manner that directly provides the substrate with moisture, without dousing the entire plant. The farina helps protect the leaves, ensuring that they can convert enough energy to stimulate the production of fragrant, lilac-blue blooms.
6) Dwarf roses (Rosa cultivars)
Who wouldn’t want a closer look at the delicate blooms of dwarf roses? These cultivars’ relatively low full height makes them great candidates for raised flower beds. Selectively bred to produce stems and blooms that maintain miniature sizes, these plants are hardy, eye-catching, and may produce just as much as blooms as their larger counterparts. To effectively enhance the appeal of a flower bed, grow cultivars with contrasting floral colors in dense rows or right next to one another.
Dwarf roses prefer nutrient-rich yet free-draining substrates. Depending on how quickly moisture evaporates in your region, they may require at least an inch (2.5 cm) or more of water per week. Full sun tends to encourage the production of a profusion of blooms in spring to summer. Mulched beds should help protect the roots from fluctuations in temperature and should promote suitable moisture retention rates.
7) Drumstick allium (Allium sphaerocephalon)
The drumstick allium, also known as round-headed garlic and ornamental onion, would be a charming addition to raised flower beds. Its pom-poms of deep purple floral heads, comprised of tiny florets and perched on top of thin yet upright stems, should enliven any arrangement while adding a touch of playfulness to its overall appearance. These unfailingly give away the presence of this species’ bulbs in late spring to early summer.
For as long as the soil is kept moderately moist throughout the growth period, the floral heads may last for up to 4 weeks. Its inflorescences, which rise to 30 – 40 inches (76 – 102 cm) above the soil, may tower over the rosettes of dwarf flowering plants. They can thus be arranged along the back, sides, or center of a diverse selection in a flower bed. Allium bulbs are quick to rot in excessively moist conditions, so the increased drainage rates in a raised setup should promote their longevity.
8) Mounding nasturtium (Tropaeolum majus varieties)
Nasturtium varieties may be mounding or trailing. The former is more suitable for flower beds, whereas the latter may require additional support or sprawl out as ground cover plants. Some of the loveliest varieties include ‘Cherries Jubilee’, ‘Cup of Sun’, ‘Orchid Cream’, and members of the ‘Alaska’ series. These sport delicate, lily-shaped foliage in various shades of bright green. The leaves of some cultivars, particularly those of the ‘Alaska’ series, are variegated.
The eye-catching blooms of mounding nasturtiums should have hummingbirds, butterflies, and bees rushing to your raised flower beds. A profusion of blooms may thoroughly cover any fading mounds from spring to summer. These come in the loveliest shades of orange, yellow, pink, and red. Fast drainage is crucial to maintain the quality of the foliage, particularly those that remain in contact with bottom substrates.
9) Black-eyed Susan (Rudbeckia hirta)
An annual wildflower that is known for its vibrant yellow petals surrounding a cone of darker florets, the black-eyed Susan is a fine choice for raised beds in cottage gardens. Maryland’s very own state flower, this species is also commonly referred to as ‘yellow daisy’. It is often cultivated in flower beds because its upright stems are fast-growing and may be quite attractive when they are densely packed.
Raised beds containing this species should be situated under full sun, where endemic pollinators are most likely to spot its blooms. Loam-based substrates, with a moderate capacity to retain moisture, are preferable, but clay soils may also be tolerated if they allow for adequate drainage. The highest bloom rates are usually observed in plots that are not excessively enriched with nitrogen.
10) Creeping phlox (Phlox subulata)
Creeping phlox, also known as ‘moss phlox’, is often cultivated in pollinator gardens, around backyard patios, and in dedicated flower beds. Though this perennial is hardy to USDA zones 2 – 9, it is typically sheared after the end of the bloom period each year. This practice minimizes the spread of diseases and encourages the rapid regeneration of new stems and leaves in the succeeding growth period.
Creeping phlox should be grown in areas that receive partial shade and ample moisture. Well-established specimens quickly spread to form incredibly colorful carpets of pink, white, purple, and magenta-colored flowers. The blooms may last for up to a month, transforming your spring garden into a haven for butterflies, hummingbirds, and bees. The trailing stems cascade over the edges of flower beds and may thoroughly hide vertical structures. For some more visual drama in the flower bed, add rocky levels and a few tufts of companion plants.
