August is often one of the most enjoyable months in the garden. Borders are at their colourful best, vegetables are producing in abundance and there is still plenty to harvest and enjoy. At the same time, experienced gardeners know that August is also the month to start thinking ahead. A little planning now will help ensure your garden continues to shine through autumn and gets off to the best possible start next spring.
Looking beyond summer
While there's still plenty to enjoy, August is the perfect opportunity to begin introducing plants that will provide stunning autumn colour, continue sowing crops for later harvests and prepare for the arrival of spring-flowering bulbs.
Ornamental Flowers, Trees & Shrubs
Continue deadheading roses, dahlias, cosmos, salvias and other repeat-flowering plants to keep displays looking their best well into autumn. Regular watering and feeding of containers and hanging baskets will also help maintain strong flowering.
August is an excellent month to begin thinking about autumn colour. Japanese Acers (Acer palmatum) are amongst the finest small trees for Irish gardens, developing spectacular shades of crimson, orange and gold as temperatures begin to cool. Nandina (Nandina domestica), often known as Heavenly Bamboo (despite not being a bamboo at all), offers attractive evergreen foliage that turns rich shades of red during autumn and winter.
Leucothoe is another superb choice, with glossy foliage taking on deep burgundy and crimson tones as the season progresses. Heucheras provide colourful foliage throughout the year and combine beautifully with ornamental grasses and evergreen shrubs to provide long-lasting interest.
If you're looking to add structure, consider evergreen shrubs such as Skimmia, Sarcococca, Pittosporum and compact Hebes, all of which perform well in Irish gardens and provide valuable year-round colour and texture.
Continue trimming lavender after flowering and lightly clip evergreen hedges if needed. Avoid heavy pruning now, as soft new growth may not have time to harden before winter.
Keep an eye on powdery mildew, blackspot on roses and other fungal diseases, removing affected foliage where practical and improving air circulation around plants.
Spring-flowering bulbs will soon begin arriving in-store and August is the ideal time to start planning your displays. Tulips, daffodils, crocus, alliums, hyacinths and species such as Erythronium 'White Beauty' all reward a little planning now with spectacular displays next spring.
We're particularly excited to be introducing some beautiful new tulip varieties this season (for us anyway), including 'Blue Diamond & Foxtrot' (Sold as 'Antique Fayre' mix) and 'Cranberry Thistle' alongside lovely daffodils such as 'Sweet Love'. We'll be taking a closer look at choosing and planting spring bulbs in a dedicated article later this month.
If you're looking for a colourful perennial to brighten your borders or container displays, then Asters are a great choice, coming in many shades of purple as well as some pink and white varieties that thrive in the autumn months - Image by grainlatte from Pixabay
Grow Your Own
For Outdoors
Harvesting takes centre stage this month, with potatoes, onions, shallots, carrots, beetroot, French beans, runner beans, peas, courgettes, and soft fruit all producing well.
Continue sowing quick-maturing crops including lettuce, rocket, spinach, mizuna, pak choi, spring onions and radishes for harvests well into autumn.
Florence fennel, turnips and oriental greens can also be sown now, while overwintering brassicas should be planted into their final positions if not already done.
Remove spent crops promptly and add healthy material to the compost heap, helping to keep beds tidy and reduce the risk of pests and diseases.
Continue watering during dry spells, particularly where autumn crops are establishing.
For Polytunnels & Greenhouses
Tomatoes, cucumbers, peppers and chillies should all be cropping heavily. Continue feeding regularly, remove lower leaves where appropriate to improve airflow and keep plants well supported.
It's a good idea now to start pinching out the growing tips of outdoor tomatoes to encourage plants to concentrate on ripening existing fruit before autumn arrives.
Continue sowing salads, coriander, parsley and basil for late harvests.
Keep greenhouse ventilation high during warm weather while remaining vigilant for red spider mite, whitefly and aphids.
Tomato plants have certainly benefited from us actually having a summer this year. Harvests have been great for weeks, but now, with plenty of green tomatoes still left on the plants, its time to pinch out the growing tip and be vigilant with removing side-shoots. It's also worth removing any remaining flowering stems as it's unlikely fruit will set and ripen before the end of the season. This way the plant can put all its energy into ripening the tomatoes that have already set. It's also worth checking the base of the plant as well to make sure no new shoots are forming there as, again, these are drawing energy away from fruit ripening. - Photo by Richard (AGC) taken on 07/08/2026 in Co. Roscommon.
Indoor Plants
Continue feeding houseplants while they remain in active growth, although towards the end of the month you can begin reducing feeding as daylight hours shorten.
Inspect any plants that have spent the summer outdoors for pests before bringing them back inside later in autumn.
Remove faded flowers and damaged foliage and continue watering according to each plant's needs.
General Maintenance
Lawns may benefit from a light feed if growth has slowed following dry weather. Continue mowing regularly but avoid cutting too short during hot spells.
Keep ponds topped up using harvested rainwater where possible and remove excessive blanket weed or dead aquatic foliage.
Collect seed from favourite flowers and allow them to dry thoroughly before storing for next year's sowing.
Take semi-ripe cuttings from shrubs such as Hebe, Hydrangea, Fuchsia, Lavender and Penstemon to increase your favourite plants.
Begin making notes about areas of the garden you'd like to improve this autumn — now is often the best time to identify gaps in borders while everything is still in full leaf.
Final Thoughts
August is a month of abundance, but it's also the beginning of the garden's gentle transition into autumn. By combining regular maintenance with a little forward planning, you'll not only enjoy the rest of this summer but also lay the foundations for colourful borders, productive vegetable beds and beautiful spring displays in the months ahead.
Get ready for the seasons ahead
Whether you're harvesting summer crops, refreshing your borders or planning ahead with spring bulbs and autumn planting, we have everything you need to keep your garden looking its very best. Visit us in-store or browse our online shop for inspiration.
