Plant of the Month August 2018


Tuberous rooted perennial.


Height and spread 40cm – 1.5metres


Aspect: Full sun


Tender to frost hardy depending on variety.


Care: Easy

Want to find it at Reveley?  Look in the vegetable garden, the mulberry tree beds and the long border at end of the main lawn.

A native of Mexico, this perennial will flower from mid-summer to the first frosts.  Colours range from deep red and purple through the pinks to white – then there are the yellow and orange varieties …. Many Dahlias, as in ‘Rebecca’s World’  pictured above, are bi-coloured.  The flowers are variously described at cactus, semi cactus, pompom, single, double, decorative, dinner plate, waterlily, anemone, peony, orchid the list goes on.  Dahlias work well in an herbaceous border, are excellent cut flowers and container plants, the large flowered varieties make striking specimen plants, and are great for the bench at the annual horticultural show. 

Dahlias are reasonably easy to grow.  Tubers should be planted to a depth of 10-15cms, in fertile well drained soil in full sun.  To over-winter, tubers will need to be lifted after the first frost has blackened the leaves.  Clean off the soil and store in a cool frost proof place in shallow boxes packed with dry sand or a peat free compost leaving the crown and 20 cm of stem exposed.  Tubers can be brought on early in pots of compost in the greenhouse from March.  Discard any part that show signs of decay.  Plant out when all danger of frost is over.  Alternatively, you can try leaving them in the ground, covered with up to 15cm of mulch such as bark.

In recent years the Dahlia has had a bit of a fashion resurgence, especially as a cut flower.  To encourage more flowers, pinch out the growing tips when plants reach a height of 40 cms.  If you want giant blooms restrict the number of flowering stems to three to five per plant.  Dead head as flowers fade and keep well-watered.

Although easy to care for, there are a few pests and diseases to look out for, number one being the slug, followed by aphids and earwigs.  Powdery mildew and mosaic virus can also be a problem.  Tubers must be properly dried and healthy before going into storage to avoid storage rot and checked occasionally throughout the winter for any bad tubers which must be removed.  Poor flowering can be caused by overfeeding or not enough direct sunlight.

Previous Months

July 2018

June 2018

May 2018

April 2018

March 2018

February 2018

January 2018

December 2017

November 2017

October 2017

September 2017

August 2017

July 2017

June 2017

May 2017

April 2017

March 2017

February 2017

January 2017

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