Perennials
The word perennial comes from the French and means long-lasting. It’s fitting because perennials are herbaceous plants that live for more than two years. Often, perennials can flower once or several times a year, for many decades. This means that you get a lot out of the time you spend growing long-flowering perennials. Perennials also create a favourable habitat for butterflies, bees and insects. Many popular varieties are cultivated plants that have been grown for a long time and have an interesting history.
How to choose perennials
There is a very large number of perennials on the market. You have a lot of options to find perennials that will fit perfectly in your garden or flower box. Here are some criteria to consider when making your choice:
- What colours suit the location where you intend to plant perennials?
- Is it a sunny or shady spot where you want them?
- When do you want the perennials to flower or be at their most beautiful?
- Do you want flowers with a strong scent?
- What is the soil like on the site?
- Do you want edible perennials?
- Do you want the perennials to spread after planting?
Once you have answered these questions, you can start looking for perennials that fulfil your criteria. It often looks good to mix several perennials in the same place.
Here are examples of common perennials categorised according to their characteristics:
- Perennials that thrive in shade: wolfsbane, meadow grass, ivy, evergreen
- Perennials that thrive in a sunny position: lavender, sage, autumn anemone, coneflower
- Perennials that flower early: yellow dock, daisy, pansies, sweet violet
- Autumn flowering perennials: autumn anemone, red coneflower, summer aster, giant verbena
- Ground cover perennials: ivy, hazel, musk madder, lungwort
- Herbaceous perennials: thyme, tarragon, rosemary, oregano, lemon balm
- Perennials with a strong scent: cowslip, ball thistle, lovage
- Hardy perennials: flock grass, red rudbeckia, winter cress, grey cat’s foot
- Perennials grown as medicinal plants: evening primrose, peppermint, red sunflower, St John’s wort
How to care for your perennials
It is difficult to give general advice for the care of perennials. It is a plant group that consists of a very large number of species adapted to completely different environments. However, here are some tips that usually work for the perennials that are common in Swedish gardens.
- Prepare the growing site by loosening the soil and removing weeds.
- Use soil from the flower shop or add compost or fertiliser to the growing area.
- Remove wilted seed heads and flowers.
- Be sure to water regularly during the first year.
- The label of the plants usually gives information about the growing depth and the distance you should keep between them.
Some hardy perennials can grow very old. However, perennials that have been in the same place for a long time tend to deplete the soil of the nutrients they need. Therefore, you may need to move perennials to a new part of the garden after a number of years, or be careful to provide the nutrients they need. If you’re growing perennials in a window box, try using varieties that are frost-sensitive and bring them inside in autumn. Keep them in a cool place – but the temperature should not drop below 5 degrees centigrade.
Author: Johanna Damm
Fact-checked by Erik Hoekstra
Last updated 2023-12-04