Pot-grown plants make handy fillers

Mixed borders that were bustling with growth and colour little over two weeks ago are looking slightly drab as plants that bloom early begin to run out of steam.

Saturday, 6th August 2016, 9:06 am
Updated Thursday, 25th August 2016, 6:42 pm
Hostas are good gap fillers in borders.

The solution is to have pot-grown replacements on standby.

Cut back spent flower stems, slot something fresh into position, and restore the equilibrium.

Of course, this entails extra work in selecting substitutes, growing them on and finding suitable accommodation until the call for action comes. But there is the option of buying something just coming into bloom from a plant centre and increasing the range you grow.

Early delphiniums are just past their best and are ready for pruning to ground level. Certain herbaceous geraniums will reach a similar phase soon, and in both cases you can anticipate secondary growth and flowering if the weather remains open. Several border perennials behave in this way. Meanwhile, treat the potted replacements as a stop-gap.

Propagating a wide range of plants becomes a way of life for keen gardeners so with a little planning you can raise a decent variety of replacements.

My current range of potted substitutes includes astrantias, hostas, fuchsias, liliums, helichrysum, lavatera, catmint and herbs. The lilies regenerate each year from bulbs which are hardy so the pots stay outdoors over winter. Buy a new cultivar each year and you soon have a collection. They decorate a patio or yard admirably until called into service elsewhere.

Astrantia can be dried and used as an everlasting flower, and hosta foliage will hold attraction long after its blooms have faded. Both form clumps as they grow and are easily propagated via division. The remainder arise from stem cuttings.

But this is a mere example of what can be done. If you’ve a favourite perennial, try it as a gap filler.