August is often a time to relax and enjoy the fruits of your summer gardening labour, but it’s also a wonderful month for planting flowers that will extend your garden’s season well into autumn and beyond. With warm days and often milder nights, August provides ideal conditions for sowing, planting and preparing for a colourful late summer and early autumn display. Whether your garden is large or small, urban or rural, knowing what flowers to plant in August ensures your outdoor space remains vibrant as the seasons begin to turn.
Late Summer and Autumn Flowering Bulbs
August is the prime time to plant autumn-flowering bulbs such as colchicum, autumn crocus and nerines. These elegant flowers bring a burst of unexpected colour when many summer blooms are fading. Planting bulbs now in well-drained soil and sunny positions ensures they will establish well and provide beautiful flowers from September onwards.
Dahlias and gladiolus can still be planted early in August, particularly in warmer parts of the UK. These bulbs will produce spectacular flowers that last until the first frosts, adding richness and texture to borders and containers.
Sowing Hardy Annuals and Biennials
August is an excellent month for sowing hardy annuals like calendula, cornflowers and nigella. These flowers will germinate quickly and bloom in late summer or early autumn, filling gaps in borders and providing nectar for pollinators.
Biennials such as wallflowers and sweet williams can also be sown now for flowers next spring and summer. These plants need to establish before the cold weather and will reward you with vibrant colour in the months ahead.
Planting Perennials and Shrubs
This is a good time to plant perennials like asters, sedums and heleniums, which provide late-season interest with their colourful and textured blooms. Shrubs such as hydrangeas and potentillas can also be planted in August to establish before winter sets in.
Perennials and shrubs planted now benefit from warm soil temperatures and usually enjoy the residual summer warmth to develop healthy roots.
Refreshing Containers and Planters
Containers and hanging baskets may need a refresh in August to keep your garden looking fresh. Remove any spent flowers and replace them with autumn-flowering plants like chrysanthemums, pansies and violas. Adding trailing ivy or evergreen foliage can provide structure and interest as the summer plants begin to fade.
Regular feeding and watering remain essential to maintain healthy, vibrant container displays during the drier summer months.
Soil Care and Watering
August can bring dry spells, so consistent watering is important, especially for newly planted flowers. Mulching around plants helps conserve moisture and keeps weeds under control. Organic mulches such as garden compost or shredded bark also improve soil fertility as they break down.
Avoid watering in the heat of the day to reduce evaporation and the risk of fungal diseases.
Tips for Small Gardens and Urban Spaces
For gardeners with limited space, August is a great time to plant compact autumn-flowering plants in pots and window boxes. Pansies, violas and dwarf chrysanthemums perform well in containers and bring cheerful colour as the seasons shift.
Vertical gardening with late-flowering climbers like clematis and ivy can add height and interest without taking up valuable ground space.
Supporting Wildlife and Sustainable Gardening
Planting flowers that attract late-season pollinators such as bees and butterflies supports biodiversity in your garden. Autumn-flowering plants like asters and sedums provide important nectar sources as other flowers fade.
Using peat-free compost and avoiding chemical pesticides helps create a healthier environment for plants and wildlife alike. Collecting rainwater for irrigation is an eco-friendly practice especially useful during dry spells.
In Summary
August is a valuable month for planting flowers that extend your garden’s beauty well into autumn. From autumn-flowering bulbs and hardy annuals to perennials and container refreshes, there are many ways to keep your garden vibrant as the seasons change. With thoughtful planting and care, your August efforts will reward you with colour, texture and life long after summer has passed.
