Border patrols; Choose from some dramatic plants to make an impact.

IT only takes some fine days and the arrival of a few plant catalogues to start me fretting about the garden.

Here's the problem. I reckon this is going to be the year of the border. I'm still continuing with new plantings and, at the same time, borders that were planted nearly 10 years ago need a major rethink.

It's an exciting prospect, but also quite a daunting one, because I'm not playing to my strengths. Some folk can effortlessly blend flowers, foliage, form, colour and season, then produce a splendidly harmonious effect.

Not me. If the colour combinations are right, it's at the price of structure. Or if I manage a good piece of textured planting, it's only to find my colours clash horribly.

There are a few tricks up my sleeve for introducing some sure-fire improvements into a border. I've learned from experience that a scattering of stiffly upright plants adds instant structure.

An injection of strong verticals can pull a flabby garden design together. Magically, they lead the eye away from a multitude of mistakes at ground-level.

Whatever did we do before we had phormiums? The New Zealand Flaxes have become increasingly popular and more widely available over the last 10 years and most folk who grow them find them incredibly useful plants.

Phormium tenax is the one that does best for me and it's never given me a moment's unease about its hardiness. The snag is, it's a giant, eventually making a sword-shaped clump up to 10 feet high.

It's a superb plant for the back of a border, or to spice up a shrub area.

But, despite its mature size, don't feel it's not for you if your garden's fairly small. It's not very fast-growing, so it stays manageable for many years.

Even at full size, it doesn't take up much room at its base and would make a grand feature even if space is limited.

For a touch of tropical splendour, introduce the stiff spiny rosettes of yuccas. The common one is Yucca gloriosa, Spanish Dagger, with an explosion of sword-shaped leaves.

It's magnificent, but not one to grow if small children use the garden. It has a razor-sharp stiff spike on the tip of each leaf, so should be placed well out of harm's way.

Better, and safer, is Yucca filamentosa. It makes a splendidly showy border plant, especially in its variegated form and, as it's evergreen, provides welcome winter colour, too.

Here's one grass I absolutely love, and it really earns its keep as an architectural upright.

It's the striped Zebra Grass, Miscanthus sinensis 'Zebrinus'. This beautiful grass is usually elegantly fountain-shaped, but I also have a form called 'Strictus' that is ramrod-straight and avery satisfying upright.These stripey sareat their best in late summer and there's nothing better to provide an effective contrast to dahlias'very messy foliage. Some of the very best sword-shaped foliage belongs to plants that normally earn their keep with their flowers.I love the stiff leaf-fans of many irises and crocosmias.There are a couple of irises that are very special foliage plants, and whose flower then come as a welcome bonus. Irispallida'Variegata' has striking green and white variegated leaves borne in tidy fans.I keep trying to grow it, but it really needs drier conditions. Still, one to look out for if you're in the east of Scotland. The one I doreally well with is the variegated form of the common yellow flagiris, Irispseudacorus 'Variegata'. The fresh foliage is striped green and butter-yellow, and no spot is too wet for it. It'll spice up your pondside, or even grow underwater, yet still thrives and colours well in an ordinary border.

There are a few flowering plants that have a strictly upright form and such narrow spires of flowers that their overall effect adds a strongly-vertical form to a mixed border.

Ligularia przewalskii has tall slender spires of yellow flowers carried showily on dark brown stems. It's a plant for a dampish place and shade, as it tends to wilt in full sun.

For the front of the border, there are narrow-flowered veronicas that can shape up those sprawling mounds of geraniums and catmint.

Most varieties of Veronica spicata have this elegantly slim habit of growth and, at 12 to 18 inches high, are perfect front-row candidates.

The German variety 'Rotfuchs' (Red Fox) is one I like very much. It has healthy grass-green foliage and the slenderest of hot pink flowers.

A near relative of the veronicas is my very favourite plant for adding a bit of height and structure to summer borders. It's Veronicastrum virginicum from north America. It grows to about five feet, but is only 18 inches in girth.

The very upright stems have whorls of leaves all the way up and are topped off by the slimmest of flowering spikes in white, pale pink, or mauvy-blue.

Without being spectacular, it's immensely pleasing.

If you plant some of these dramatic plants this year, you'll have acquired what fashionable garden designers call "texture".

So, give it a try. You'll find even a few can create an incredible impact.