August Plants

August got off to a good start weatherwise, but the weekend rain from the tail end of Hurricane Bertha has at least given the gardens a good watering!

Here’s my top ten flowering plants for August:

image of agapanthus plant

1. Agapanthus – 

African Lily – an exotic looking plant with impressive, large rounded heads of blue or white flowers August – September above shiny, strap-like foliage. They tend to flower better if root-bound, so are very good in pots. Protect from winter frosts to ensure survival.

image of campsis plant

2. Campsis – 

Trumpet Vine – another candidate for the mediterranean-style garden, this climber has attractive pinnate foliage with good autumn colour and large salmon-red trumpet-shaped flowers August – September.

image of canna plant

3. Canna – 

Indian Shot – although not hardy, this is a popular plant for the tropical scheme, with its large, bold leaves, often streaked with purple or red and brightly coloured flowers in summer. Lift before the first frosts or take pots into a cool greenhouse.

image of caryopteris

4. Caryopteris – 

often known as the ‘Blue Spiraea’ for the similarity in the shape of the flowers, this is a small, compact, rounded shrub with lance-shaped grey-green leaves and dense clusters of deep blue flowers August – September. It doesn’t grow too big and is ideal for the front of the border for late summer colour. In spring cut the stems down to just above ground level.

image of echinacea

5. Echinacea – 

Purple Coneflower – a reliable perennial and an old favourite, with wonderful pink daisy-like flowers with a prominent, darker central cone July – September. Dead-head, if you can, to prolong flowering.

image of echinops

6. Echinops  – 

Globe Thistle – as the common name suggests, this easy to grow, back of the border plant has thistle-like foliage and globular steel-blue flowers July – September. If you cut the flowers before they are fully open, they can be dried for winter decoration.

image of hibiscus

7. Hibiscus – 

Tree Hollyhock – a large, but slow-growing shrub with lobed dark green leaves that are late to appear in spring, and large blue, pink or white trumpet-shaped flowers August to October – invaluable for late summer colour.

image of perovskia

8. Perovskia – 

Russian Sage – so named because its delicate, silvery-grey foliage has the fragrance of sage. From a distance it looks something like an oversized lavender with erect stems carrying lavender blue flower spikes August – September – beautiful.

image of romneya

9. Romneya – 

Tree Poppy – once again the common name tells us all we need to know – with fragrant, white, poppy-like flowers the size of saucers from July to October and attractive blue-grey foliage, it is a shame this shrub is not used more.

image of thalictrum delavayi

10. Thalictrum delavayi ‘Hewitt’s Double’ –

with tall slender stems, delicate fern-like foliage and tiny, fluffy, pompon-like mauve-pink flowers midsummer to early autumn, this is another under-used plant. The books will tell you it grows to about a metre tall, but in our garden it’s at least two! Great for the back of the border.

August Tips & Advice

1. It’s easy at this time of year for everything to start looking a bit tired so continue with watering, feeding, weeding and dead-heading to keep everything looking good.

2. As for previous months, top up ponds and water features as evaporation occurs.

3. Continue to check your roses (and other plants) for pests and diseases and treat promptly if you find anything.

4. Check your climbers to make sure ties are not constricting growth or cutting into stems. Do the same for young trees.

5. If you are lucky enough to have tree ferns and we do get dry weather – don’t forget to spray their trunks and crowns so that they don’t dry out.

6. If you have bearded Irises that need dividing because they are overcrowded, do it now, lifting the whole clump and pulling away the new rhizomes and discarding the old bits. Re-plant the new rhizomes firmly, leaving half exposed above ground level as they like to bake in the sun. Don’t forget to water though!

7. Cuttings may still be taken now of Fuchsias and Pelargoniums to provide plants for next year. You can also take cuttings of Rosemary and Thyme. Try not to let other herbs flower and go to seed, by cutting and using regularly – fresh herbs are such a valuable source of vitamins, we should all try to grow at least a few.

8. August is also a good time to prune fruit trees that have become overgrown and unproductive. It will open them up and encourage fruiting next year. Espalier and fan-trained fruit trees should be pruned late in the month too.

9. Autumn and winter flowering bulbs such as Crocus and Muscari can be planted now, as can Cyclamen. You may also like to look ahead at bulb and seed catalogues for next year!

10. Give your lawn its final summer feed this month. Don’t do it any later as autumn applications will just encourage lush growth, leaving the grass more susceptible to disease in the cooler, wetter autumn weather.

Finally, if you are going away on holiday, don’t forget to make arrangements for your house plants to be watered.

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