August Gardening Tips

What a summer it’s been! A warm spring rolled seamlessly into a summer filled with back-to-back heatwaves. While this hot, dry weather has helped keep fungal issues at bay (a welcome change from last year), it’s also brought a surge in aphids. Thankfully, the ladybird population has risen to the challenge – nature always finds its balance.

August is a popular time for holidays so if you’re heading away, now’s the moment to put a care plan in place for your garden (as discussed in last month’s blog). With that in mind, here are some timely tips to help your garden thrive through the dog days of summer.

1. Harvest early apples and pears – Check if your fruit is ready by gently twisting an apple or pear in your hand. If it comes away easily with the stalk intact, it’s ripe. Another giveaway is finding a few fruits on the ground below the tree.

2. Lightly trim lavender – Now’s the time to tidy up lavender by snipping off old flower spikes and about 2.5cm of leafy growth from the shoot tips. This encourages new side shoots, keeping the plant compact and bushy.

3. Prune rambling roses – Once they’ve finished flowering, prune back side shoots to one or two buds from the main stem. Remove older woody stems entirely to make room for fresh growth and tie in new shoots to shape next year’s blooms.

4. Sow green manure – If you’ve got vacant soil, sow green manure crops like mustard or rape. These fast-growing plants can be dug in before flowering to add organic matter, improve structure and prevent nutrient loss over winter. Simply scatter the seeds and rake them into the soil surface.

5. Maintain the greenhouse – Keep your greenhouse humid by damping down the floor on hot days – this helps plants and controls pests like red spider mites. As nights cool toward the end of the month, close vents and doors in the evening to retain warmth. Remove shading by late August to maximise light as the days shorten.

6. Cut back collapsed perennials – Heavy rain can flatten tall perennials like Achilleas. Cut them back to allow sun and air to reach smothered plants. Many will respond by sending out fresh growth and even flowering again in autumn.

7. Tidy up hardy geraniums – If you haven’t already, give hardy geraniums a good cut back now. They’ll bounce back with new foliage and may even bloom again before the season ends. Feed and water them well to encourage regrowth.

8. Water and feed containers regularly – In hot weather, container plants may need watering more than once a day. Keep them blooming by feeding weekly with a high-potash fertiliser (like tomato feed).

9. Plant bulbs for Christmas blooms – It might feel early but now’s the time to plant prepared hyacinths and other bulbs if you want festive flowers for Christmas. After planting, store them in a cool, dark spot (shed or cellar) for 8–10 weeks. Keep the compost just moist and once shoots appear, move them indoors to stimulate flowering.

10. Top up water features – In a heatwave, pond water levels can drop quickly and oxygen levels with it, especially if the water is still. Top up regularly and spray the surface to boost oxygenation. This is essential for fish but also benefits all aquatic life.

If you have any further questions or would like some assistance with your garden, then visit our Nicholsons Garden Management webpage.