Why has my kniphofia plant not flowered in the last three years?

Whether you're a gardening beginner or expert, Irish Examiner columnist Peter Dowdall has the answer to your questions

QUESTION

I have had a kniphofia (yellow, but not sure of the variety) for five years. It has not flowered for the last three years in spite of being in full sun. 

This past spring I fed it several times with tomato food which gave no result. What should I do?

ANSWER

When a perennial which is growing in the correct conditions, such as this kniphofia, in full sun, stops flowering, it is normally for one of two reasons: Either a nutrient deficiency or it needs some rejuvenation.

Potassium is the nutrient mainly responsible for flower and fruit production and tomato food is rich in both potassium and phosphorous. 

Feeding with tomato food didn’t work and so I would certainly look at the second option. By lifting the established clump during the winter and dividing it into several plants you are not only giving yourself more plants but you are also giving a whole new lease of life to the original clump. 

Do this over the next month or two and I am certain that your kniphofia will give you blooms aplenty next summer.

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