Longest Flowering Plants For your Garden
Updated: Aug 31
People always ask how they can create a long season of colour in their gardens. As gardeners and garden designers, how we achieve this really depends on how much time you have for garden maintenance and how skilled you / your gardeners are at maintaining your plants. How much room you have can also be a factor as if you don’t have a huge outdoor space, then you need the plants you chose to work as hard as possible and that could mean that you want the longest flowering plants, if colour is what you’re aiming for. If you have the luxury of space, then you can settle for plants with a shorter flowering season but more variety of species and flower form so the colour continues from one plant to another through the year.
Here’s a list of some of the longest flowering plants for your garden which are used by gardeners and garden designers. New cultivars are appearing all the time but this list is tried and tested as some of the longest flowering plants that I’ve come across.
Erigeron karvinskianus - A low growing, long flowering evergreen daisy for front of the border. It’s a clump forming perennial that grows to approximately 50cm wide x 25cm tall and can flower from May until October. Give it a clip at the end of its flowering season to tidy it up, note that it does tend to self seed so weeding little and often to keep unwanted seedlings in check is a good idea. Prefers free draining soil and full sun.
Centranthus ruber - A long flowering plant, commonly known as Valarian. This useful perennial plant can be grown in a traditional border setting, grown in cracks in walls, or used in green wall plantings. 60cm wide x 1m tall, it will flower from May to October. Dead head the spent flowers before it goes to seed. Prefers free draining soil in full sun.
Gaura lindheimeri ‘Whirling Butterflies’ - Swarms of butterfly like, pink tinged, white flowers float about on wiry stems from June to October. A fairly short lived perennial growing to 50cm wide x 75cm tall. Prefers free draining soil and full sun.
Salvia nemorosa ‘Ostfriesland’ - I love Salvia and would plant this in every garden, conditions permitting! With violet flower spikes which are magnet for bees, it will flower from June to October if you dead head the spent flowers regularly. 50cm wide x 60cm tall, it needs free draining soil and full sun.
Coreopsis grandiflora ‘Early Sunrise’ - Bright yellow flowers on individual stems from July to September. Dead head regularly to extend the flowering season. Looks best in groups of 3, 5 or more, attracts butterflies and is a great cut flower too. It is short lived at about 3 years but if you divide every couple of years you can reinvigorate and extend its life span (and get more plants!). 60cm wide x 60cm tall. Flowers best in full sun but will tolerate part shade, grows in most soil types.
Verbena bonariensis - A tall plant at around 1.5-1.8m, it has purple flowers which float above the ground on strong stems which will stand all winter. One of my favourite longest flowering plants, it will flower from June to October, it isn’t completely reliable as a perennial so treat it as a biannual. It does self seed though in the right conditions. Prefers free draining soil but will tolerate most soil types. Needs full sun, otherwise it tends to lean over!
Achillea millefolium 'Lilac Beauty' - Multiple flat heads of flowers which add good contrast to spikes or balls of flower on other plants. 60cm wide x 80cm tall. Flowers from June to September. Tolerates most soil types. Needs full sun.
Rosa - Roses are one of the best long flowering plants for heavy soil. There's nothing is quite like a rose for flower production, scent and impact in the garden. You can dig them up and move them around to your hearts content in winter. Just learn how to prune them and give them plenty of nutrients and they won’t let you down. Most soil types, will flower best in full sun but works in part shade. Chose a cultivar that is disease and pest resistant as well as repeat flowering.
Hydrangea paniculata ‘Limelight’ - Large white, tinged lime green, coned flower heads from June to October on this deciduous shrub. It can flower from July to November, will grow to 2.5m x 2.5m if left unchecked. Prune back in early spring to keep it smaller. Full sun to part shade, doesn't like to dry out.
Note that most of these long flowering plants need or prefer full sun. Producing flowers takes a lot of energy which is only available to plants through photosynthesis. So more sun allows for more flowers. If you have a shady garden it might be best to focus on leaf and plant form rather than flower colour.
Please always remember to check that plants are suitable for the conditions in your garden before spending your hard earned money. Soil conditions and the available sunlight can dramatically affect a plants flowering performance!