BRIAN KIDD: How to get herbaceous plants to bloom again

My word, after a long spell of dry weather when everything seemed to be struggling, rain saved the day and our herbaceous border has grown like mad, weeds and all.

Saturday, 5th August 2017, 7:06 am
Updated Tuesday, 12th September 2017, 11:17 am
Dead-head your delphiniums and you should get another show in the autumn.

Our delphiniums were very slow to come into bloom this summer but they have now been the best ever.

We put in single canes to each flower stem so the foliage hid them. The trick is to cut off the top of the canes just below the spire of flowers. The plants have now been cut back leaving just two feet of the magnificent foliage, the soil has been forked to a depth of four inches and the plants given a good soaking of Maxicrop Complete liquid plant food because we would like more spikes of blooms in October.

Lots of herbaceous plants won’t come into bloom again after the first flush of flowers but there are quite a few which will continue to bloom if the plants have all the dead flowers removed; a very good example is an erigeron called Elstead Pink and erigeron Blue Waves.

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These bloomed in June and were cut back hard leaving just the rounded shape of foliage, given some of the feed I just mentioned, and today they are in full bloom again and will continue into autumn as long as the dead flowers are removed regularly.

As you know penstemmons are also wonderful repeat-flowering plants. Herbaceous phlox will bloom again if the main head of dead flowers is taken off down to a side shoot with tiny flower buds. A nice drink of that plant food will do the trick.

Something was eating the leaves on just one hosta called Diana. We went out to have a look after dark and found the little culprits – earwigs. They were given the size 10 treatment on smooth paving. We are now trapping them by upturning a clay flower pot with rolled up newspaper inside and placed on a stick eight inches tall and placed alongside the hosta. The earwigs eat all night and then crawl into the newspaper which is unfolded in the mornings so they too get the size 10 treatment. It is a bit disappointing to find there are only one or two each day but the hosta hasn’t any more holes!

We had another problem, huge rips in the leaves of the ligularia called Desdemona.

We both thought it couldn’t be slugs or snails because the hedgehogs eat them at night. I watered the soil and put down three rhubarb leaves one on top of the other on the ground alongside the Ligularia, had a look the following morning and found three large snails.

I don’t like killing snails, they seem to be too beautiful, so they were taken to a piece of wasteland full of docks, three miles from where we live and I feel sure the are very happy there.

It’s no good throwing them over to the neighbour’s garden.

Snails are known to have homing instincts and they return; but hopefully they don’t normally slide three miles...


It’s time to plant nerines, amaryllis and colchicum bulbs. Choose somewhere they can bask in the sun and they will give much pleasure in the autumn.

They may not be at garden centres yet. They are usually in dry packs with a picture on the front. I mention this early because they go quickly.