Water well for healthy hostas

With a top temperature of 26.3C in the shade last Thursday, I reckoned that summer had arrived and like us, many of you will have been planting out beds, tubs and baskets.

To be able to look forward to a colourful display in a week or two when the plants have settled in and begun to cover the bare surfaces you must pay attention to watering.

Any soil which has been disturbed at planting time, though the plants may have been firmed in well, will have dried out in the interim.

Whether you have irrigation systems or stick to watering by hand, the important point to remember is that the job has to be done in the cool of the morning or in the evening for the plants to benefit fully. Avoid watering when the sun is at its height.

I have already drawn attention to the technique this season, reminding new gardeners particularly that the water is best used by applying it directly to the soil surface with a “rose” on the end of the hose pipe or watering can.

So often you see these idyllic pictures of people standing wafting a hosepipe about as if they were casting a fishing rod. That is so misleading. Firstly, if it is a sunny day, there is danger that the water landing on young tender foliage will scorch it. Secondly, it is a very inefficient way of getting the much-needed water to the plant root systems – it’s a drink they need, not a shower.

I have some perennials, mainly hostas, in pots on a gravelled area at the front of the house which faces east. They get the morning sun and frankly, if they were not being watered regularly – late in the day when they are in the shade – the roots would be cooked.

At this time, I tend to add some liquid feed to them because there is no room at the top of the pot to topdress with fresh soil when, of course, I could add granular fertiliser.

I have mentioned these hostas before because I have one or two planted through that gravelled area.

As a result, I do not have a slug problem with either technique.

Coming back to the annual summer bedding plants, I have the first question of the season about geraniums: “My geraniums are not looking so good this year, there are very few flowers.”

That comment took me back a good few years to my dad, who was a public parks gardener almost all his working life, ending his career as superintendent of parks in Helensburgh and district.

He loved planning the annual bedding schemes for Hermitage Park and the flower beds in the town centre. One of his favourite plants was the geranium and in particular, a variety called Paul Crampel, which has a bright scarlet red flower.

Regardless of our weather conditions, it was a reliable performer.

In those days the plants were grown like dahlias – in other words, they were all raised from cuttings.

Mature plants were lifted from the flower beds in September to make way for the wallflowers and potted up to be over-wintered in glasshouses.

In the following spring they would produce the young shoots, to be taken as cuttings, producing the young plants for the following summer.

This was standard practice the length and breadth of Scotland.

Nowadays, of course, we use plants grown from seed and that is a story for another day.

To my point – I clearly remember dad’s comments about geraniums on return from a summer holiday in Bournemouth.

“Their geranium displays were one-third green (foliage) and two-thirds flower,” a reference, of course, to the flower beds viewed from a little way off, whereas outside our window in Helensburgh, the beds of geranium were two-thirds green and onethird flower.

Got it?

The difference was in light and temperature.

Geraniums originate form southern Europe and we were several hundred miles further north than the English south coast.

I do believe that those of us who grow the geranium (botanical name – Zonal pelargonium) over the winter months and into spring will have plants that are reluctant to flower until they have thrown off the dark and short days of winter and early spring.

I wonder what will happen as climate change begins to affect our plants because, have you thought about it, the long/short, day/night pattern won’t change.

How will the likes of geraniums react to that, I wonder, because I am pretty sure it is already affecting the performance of some of our shrubs.

Before leaving the subject, to answer the original question: repot the geraniums in some fresh compost or give them a wee tot of Tomorite – either will give them a bit of a gee-up.

Did you see the publicity about Scotland’s Summer Garden Festival?

This is another initiative, a bit like the Virtual Chelsea Show caper organised by the RHS.

In this instance, it is organised by Lady Catherine Erskine at Discover Scottish Gardens.

For many, this could be the breath of fresh air you crave.

Starting from Saturday June 13 and running until August 15, it features a number of gardens throughout Scotland. For example, Lady Gordon Lennox at Gordon Castle on cut flowers; Des Cotton at Glamis Castle on summer pruning; old colleague Lesley Watson at Hopetoun GC on art in the garden.

There’s more.

■ For details visit discoverscottishgardens.org/summergardenfestival

THIRSTY PLANT: Hosta Sleeping Beauty - this variety of plant needs watering in shade, late in the day to avoid the roots being ‘cooked’

Hosta Whirlwind is aptly named with its whirling variegated leaves

A potted hosta shows off its beautiful flowers