Herbaceous perennials are a staple of any garden design. They are particularly useful plants for beds and borders. But many perennials also grow well in pots, making them ideal for container gardening projects.
What is a Herbaceous Plant?
Simply put, herbaceous plants are those with non-woody stems. Herbaceous plants can be perennials, annuals, or biennial plants. They are generally easy to grow, with above-ground growth taking place during the growing season each year. They reach their full potential and flower within just one growing season. Unlike shrubs and trees, herbaceous plants die right back to ground level at the end of the season. Check more Perennials out at Gardeners Dream.
What is a Perennial Plant?
Perennial plants are those that come back every year. To be classed as a perennial, a plant lives for more than two years, though some live for much longer. Some perennial plants are evergreen and provide year-round interest. Others are dormant over winter and sprout back to life the following spring. Perennials are generally hardy enough to withstand harsh winter temperatures. Therefore, they are long-lived plants compared to annuals and biennials.
Defining Herbaceous Perennials
With those points in mind, herbaceous perennials are plants with non-woody stems that live for three or more years. Herbaceous perennials die back below ground level at the end of the growing seasons. However, their roots remain intact, hibernating under the ground until early spring, when they resume plant growth. Above-ground growth, including young foliage and flowering, happens over the course of spring and summer before the plant fades again towards the end of autumn.
Examples of Herbaceous Perennials
A huge range of plants fall under the umbrella of herbaceous perennials, with many non-woody plants fitting the bill. Several boast attractive foliage, while some produce stunning floral displays. Yet others are valued for their culinary use.
Hostas are fast-growing leafy herbaceous perennials that grow well, even in shaded parts of the garden. They are ideal for borders and container gardening, suiting a range of pot sizes. Some hosta varieties produce racemes of white flowers on tall stems in summer.
Valued for their large daisy-like flower heads, coneflowers bloom in late summer and are a magnet for bees, butterflies, and other pollinators. They thrive in full sun and prefer well-drained soils, tolerating drought well.
These low-maintenance perennials have a long flowering period, producing bright yellow blooms late into the season. Rudbeckia prefers a sheltered spot in full sun or partial shade and grows well in most moist but well-draining soil types.
Boasting pretty pink, red, and white flowers, peonies are a popular choice of perennial plants for borders and flowerbeds. Planted in full sun, they bloom for weeks on end from late spring to early summer.
Ornamental sage flowers for months from early summer right through to autumn. The small flowers are tubular in shape and grow on tall stems, attracting bees and butterflies to the garden. Some salvia varieties are tender perennials that do best in pots that can be moved inside over winter, while others are much more hardy and can survive outside all year round.
When to Plant Herbaceous Perennials
The best times of year for planting perennials are spring and autumn. Choose a day with no frost forecast to give new plants the best chance at survival. During spring and autumn, the ground should still be soft with plenty of moisture to help the roots establish.
Where to Grow Herbaceous Perennials
Traditionally, these plants are grown in a herbaceous border. However, they work well with other plants, so there’s no need to keep them separate from the rest of the garden. Herbaceous perennials are ideal for complementing shrubs and bushes and adding greenery around summer flower displays. They can be used to add structure and fill gaps in flowerbeds. Many herbaceous perennials flourish in pots and are ideal for container gardening.
The short answer is that you can grow herbaceous perennial plants almost anywhere!
How to Grow Herbaceous Perennial Plants
Most herbaceous perennials are undemanding and easy to grow. Different plants have different requirements regarding watering, light, and soil type but you’ll find your choice is widened if you have a sunny, sheltered spot in moist but well-drained soil.
Water herbaceous perennials regularly during dry periods, being careful to water only the soil and not the foliage. Perennials usually thrive without much fertilisation, but an annual feed of all-purpose liquid plant food helps keep them healthy and growing well. Regular deadheading of spent blooms maintains the plant’s attractive appearance and promotes further flowering.
It’s worth noting that perennial plants grown in pots and containers need a little extra TLC. During dry spells of summer weather, these plants need watered more often than those planted in the ground. Additionally, tender perennials may need pot insulation to help protect the roots against frost damage.
Lifting and Dividing Herbaceous Perennial Plants
Lifting and dividing perennials is one way to get more plants for free. But it also helps keep perennial plants happy and healthy, rejuvenating them to encourage fresh new growth. Dividing perennial plants promotes more reliable flowering and a better show each year.
Like planting perennials, the best times to lift and divide them are in spring and autumn. Unless you’re dividing irises, don’t be tempted to lift herbaceous perennials during their prime flowering period. Spring-lifted plants will grow quickly in their new spot, while plants divided in autumn have plenty of time for their roots to settle in before spring.
Perennials suitable for lifting and dividing include hosta, agapanthus, verbena, salvia, and ornamental grasses.
How to Lift and Divide Herbaceous Perennials
Lifting and dividing is relatively easy to do and doesn’t take much of a green thumb. Loosen the soil and use a garden fork to gently remove the plant from the ground. Take care not to damage the roots, which can grow wider than the plant’s above-ground growth.
Examine the plant roots and carefully tease them apart. Some plants, particularly those with a sturdy crown, will need the help of a spade or a sharp knife to cut the root system. Don’t be afraid that you’ll hurt the plant – you’re actually helping to keep it healthy!
Replant the new individual plants and water them in well. Getting the plants back into the soil quickly ensures they don’t lose too much moisture and don’t get stressed by the experience. Large clumps can get replanted in the garden, but you may wish to start smaller sections in pots until they are well enough established to thrive in the ground.
Slugs and Snails
It’s common knowledge that slugs and snails love to feast on leafy herbaceous perennial plants. This can leave attractive foliage covered in unsightly holes in growing perennials, somewhat spoiling the overall effect.
The easiest way to deter slugs and snails from your perennial plants is to cover the surrounding soil in pieces of gravel or broken eggshells. Creating a jagged, uneven surface makes it difficult for crawling creatures to reach the greenery. Alternatively, slug pellets are available to help remove more persistent pests from the area.
Herbaceous perennials are a staple of most gardens, providing colourful flowers, leafy texture and architectural interest from early spring through summer and often into autumn.