How to choose and plant colourful plants for cool summers

Cool summers are a joy for people and plants alike. Here are some quick tips for designing a garden that will thrive during a cool summer.

Some of the advantages of gardening in northern latitudes or at higher elevations in mountainous regions include low humidity and delightfully cool summer days that seldom exceed 27°C (80°F). Additionally, many coastal areas benefit from cooling lake or ocean breezes.

• In these locales, if you have a sunny garden site and crave a sumptuous, traditional flower garden, you're in luck.
• Colour balance is a crucial factor of garden design, and many people quickly discover that they have favourite colours when it comes to foliage and flowers.
• In sunny sites, bright, saturated colours usually show up best, whereas white and light pastels are easily lost in the sun's glare. Towering mauve-flowered foxgloves, deep pink and red hollyhocks, and the huge, fragrant magenta or deep pink flowers of peonies are the pride of sunny gardens in early summer.
• High summer belongs to colourful annuals, combined with pink phlox, warm-hued daylilies and lavender-blue catmint.
• Late-summer colour is often even stronger, with the deep blue flowers of monkshood, the golden flowers of rudbeckia and the vivid pink flowers of turtlehead blooming just ahead of those of bright yellow sneezeweed.
• In autumn, cool blue and purple asters bring the blue of the sky down to earth and unite it with warm-hued gold and burgundy chrysanthemums and trees ablaze in brilliant seasonal red and gold.

Some other plants that thrive in cooler temperatures are:

1. Bluebeard
2. Borage
3. Buddleia
4. Calendula
5. Candytuft
6. Centaurea
7. Cosmos
8. Crocus
9. Daffodil
10. Dianthus
11. Dusty miller
12. Euonymus
13. Euphorbia
14. Flowering cherry
15. Forsythia, geranium
16. Golden chain tree
17. Grape
18. Gypsophila
19. Hen and chicks
20. Holly
21. Iris
22. Japanese maple
23. Juniper
24. Lily
25. Lilac
26. Monkshood
27. Oriental poppy
28. Ornamental cabbage
29. Ornamental grasses
30. Pansy
31. Pincushion flower
32. Rose
33. Smokebush
34. Snapdragon
35. Statice
36. Tulip

Though temperatures in cool-summer areas of the country are perfect for summer gardening, because plants are less likely to wilt under the sun's glare and the soil is more likely to retain sufficient moisture for plant roots, the season often seems painfully short. Frosty nights may persist well into spring, delaying planting until summer is nearly underway. Invest in perennials, shrubs and hardy bulbs.

• These plants, which are in the ground ready and waiting for spring, are a reassuring presence, making it easier to wait for warm planting weather before setting out summer annuals.
• Fortunately, there are a number of cold-tolerant annuals that can be planted before the last frost has passed. Some of these are calendula, dusty miller, lobelia, pansy, snapdragon and sweet alyssum.
• Yet because bedding plants are often grown in heated greenhouses, they fare best in the garden when they become accustomed to outdoor conditions gradually, over a period of two weeks. This process, called hardening off, initially involves setting potted plants outdoors in a sunny, protected spot for a few hours each day for a week.
• Then, the week prior to planting, allow them modest exposure to chilly winds and cool nights, but bring them indoors if hard freezes threaten. By this time, their stems will have become sturdy and new leaves will be a bit thicker and more frost-tolerant. The move into cold soil and chilly air will only cause a modest shock to the plants' roots.

Keep these tips in mind and plant a beautiful garden that will thrive in a cooler environment.