The heat is on - so how does your garden glow?

The sun is here, our plants are thirsty, and OLIVE RYAN has some tips on watering them
The heat is on - so how does your garden glow?

Herbaceous perennials form billowing mounds of texture and colour at the height of summer

WHAT a difference a week makes in the garden. The plants are beginning to get a bit thirsty as they forge ahead with flowering!

New growth has slowed down for now, with water a limiting factor. The sunshine is making everything look good and herbaceous perennials are sparking in the glorious weather.

They really mark the arrival of the growing season as they emerge from the soil in spring, after lying dormant beneath the soil over winter. They put on growth at speed once the temperatures rise and get to their blousiest peak in July and August, when they bubble out of beds and borders, producing a fantastic colourful display which makes all of the work dividing, moving, mulching, staking and feeding throughout the year worth the effort.

Herbaceous borders are a great resource for wildlife, providing plenty of nectar and pollen for insects and pollinators, a great feeding habitat for small birds that regularly feed on seed heads and invertebrates in the soil also.

Depending on the size of a border, they have been known to attract hedgehogs, field mice, pygmy shrews and frogs in damper spots, as the plants create a layer close to the soil that is good for these small creatures to go about their business!

We are becoming more mindful of growing plants that suit their planting location, soil type and micro-climate. It just makes sense, as it means when a plant is happy, it will grow well and require minimum intervention from us gardeners.

Growing plants that are drought- tolerant is certainly a greater consideration in recent years, as our weather grows more unpredictable. Good herbaceous perennials to start with include Nepeta, Lavender, Salvia, Agastache, Geum Echinacea, Sedum, Eryngium, Agapanthus, Geranium and Verbascum.

Keeping the soil well mulched will help minimize evaporation from the surface of the soil, and help plants stay healthy, ensuring a better reserve of moisture is available.

Once plants are established in the ground after a year, it should not be necessary to water regularly as roots should be able to source it independently, except during a drought.

Even then, you’ll notice some require water more than others, taller plants may show signs of wilting before others as the water has quite a height to travel to the top.

In recent years, I find some spot watering in a drought is more effective than putting a sprinkler on the whole border, as this can have the effect of knocking all of the blousey foliage and flowers, particularly later in the summer. Also, spot watering can be done with a dish of waste water that might otherwise be poured down the sink, making it a more sustainable approach.

Alstromerias are some of the best herbaceous perennials, producing flowers from May till the first frosts. Some of the best herbaceous plants for me this year are Alstromeria ‘Summer Snow’, producing white/cream flowers great for cut flower arrangements, growing to a height of about 60cm, with a similar spread.

Salvia ‘Royal Bumble’ is a great pop of colour with its vivid red flowers throughout the summer months, take cuttings in autumn as insurance as a severe winter could kill the plant.

There are such a range of good salvias and many are a great late summer addition to the garden.

Salvia sclarea var. turkestanica ‘Vatican White’ is a new one for me this year, and grown from seed, so as a biennial it will not flower until June/July next year. It has beautiful soft grey foliage and pure white flowers surrounded by large white bracts and is particularly recommended for poor and dry soil. A great plants for bees and butterflies also.

Creating a pleasing plant combination is all about putting together different colours, textures, and heights. Every year it changes as plants grow and self-seeders appear.

We can plan to create a certain planting style in our gardens, and sometimes the best combinations are happy accidents when self-seeders pop up.

Choosing plants that have a long flowering season and are easily established and cared for will make the job of a great-looking garden so much easier this summer, so choose wisely when picking up plants at the garden centre or plant fair.

One of the best aspects of visiting gardens now is spotting worthwhile plants to add to our own gardens.

The West Cork Garden Trail comprises 23 gardens, beginning in Cork and Kinsale, heading west to Clonakilty, Roaring Water Bay, Sheeps Head and Bantry, and finally onto the Beara Peninsula. See for more.


Plant of the Week Anisodontea capensis, or cape mallow, is a great plant, flowering for most of the year in milder parts of the country, and it is loving our current spell of sunshine.

A native to South Africa, it will survive outdoors over winter in a sheltered spot but may need to brought into the glasshouse if there is risk of severe frosts.

It can be propagated easily from cuttings and would be considered a sub shrub. It can get to over a metre in height and spread and provides great colour in the garden throughout the year when planted in the right spot.

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