Gardening: How to increase your stock of perennials | Brian Kidd

At the moment they’ve died down but underneath the soil the shoots which will produce flowers in the summer are just starting to emerge. But now is the time to dig them out to put new life into the border.

Dig out a huge clump of the herbaceous plants and plonk the roots on to a large flattened cardboard box.

Take two garden digging forks, thrust the tines into the roots and push the handles together, this will break up the clump.

You will get the best results from the parts of the clump around the edges because they have been growing in soil with sufficient fertility. The centres of the plants are almost worn out because all the nutrients have been taken out of the ground by the plant.

Once the outer pieces are sorted the area where they are to be replanted needs fertiliser. Blood, fish and bone is a good choice as it is cheap, but if foxes visit the garden they may dig around trying to find what they think is food. A more suitable food is Vitax Q4 pelleted fertiliser or something similar.

Pelleted fertiliser remains active in the soil for a couple of months because it breaks down slowly. Use up to four ounces a square yard and work in with a garden fork before planting. The ground is still wet after all the bad weather so it may not be necessary to water after planting.

What about some new plants? Remember, herbaceous plants grow rapidly and any bought in pots will flower this summer. Prices vary. For example, a large pot will cost between £3.99 and £4.99 but often the same varieties are available in smaller pots for only £1.99, a good buy. They will flower this summer but by this time next year they will be even bigger than those in the large pots.

I am very fond of phlox, Michaelmas daisy, ladies’ mantle, golden rod and hardy geraniums which smother the soil’s surface. All of these will be split up in the next couple of weeks. This job could have been done earlier but it isn’t a good idea to even consider it when the weather’s unsuitable. Choose a nice day so you can enjoy working out there rather than battling against the elements.

If, having read this, you’re wondering if some of these plants can be grown from seed, the answer is yes. Try something you’re not familiar with. Study the pictures on the seed packet and then read the notes on the back. In particular, check the heights particularly if your garden is tiny or you like growing things in tubs.

Now, most importantly, look for the code in heavy print and check the letters HP are there. They don’t stand for hire purchase, they mean herbaceous perennial which ensures they are hardy and will last many years.

In May, the best time to sow the seeds, I will write about hardy perennials and raising them from seed, no greenhouse required.

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