We've always had a soft spot for true blue flowers in the garden, as they can be so challenging to find in nature. The aptly named Geranium Johnson's Blue has been one of our absolute favourites for years now - and for good reason!

In our opinion, this is one of the best blue-flowered geraniums you can get your hands on. It forms these wonderful dense, spreading mounds that typically reach about 30-60cm in height while spreading a generous 60-90cm across.

The wildlife-friendly credentials of this plant are impressive as well. We've noticed that even in gardens plagued by deer and rabbits, this tough little perennial stands its ground admirably. This resilience is partly why we recommend it so often to gardening friends who want low-maintenance options.

Here at the nursery, we always advise customers to give Johnson's Blue a good chop after its magnificent June flowering. Trust us on this - it makes such a difference! The plant responds beautifully by producing fresh foliage and often a second flush of those lovely blue flowers, ensuring your garden stays colourful throughout the growing season.

 

What Makes Geranium 'Johnson's Blue' Stand Out

We've been growing Geranium 'Johnson's Blue' for years now at the nursery, and we're certainly not alone in our admiration for this plant. This exceptional, hardy perennial has several standout features that make it a winner in almost any garden setting.

Unique Lavender-blue Flower Colour

The flowers of Geranium 'Johnson's Blue are truly its crowning glory. When we first encountered these blooms, we were immediately struck by their remarkable colour - a deep lavender-blue that's increasingly rare in the garden. These saucer-shaped flowers measure an impressive 5cm in width and create such a stunning display that visitors to our nursery often stop in their tracks to admire them.

What we find particularly enchanting is how each flower features rounded petals with those distinctive dark veins running through them, adding real depth and character. If you look closely, you'll notice something rather special - the lavender-blue petals become noticeably paler towards the centre, creating this beautiful ombré effect that really catches the eye.

Many experts consider this variety one of the bluest and best geraniums available, which is saying something given how many cultivars there are to choose from!

Compact, Clump-forming Habit

The growth habit of this geranium is another reason we are so fond of it.

One of its most valuable qualities, in our experience, is how rapidly it forms a dense carpet of foliage. This makes it excellent for:

• Creating effective summer ground cover
• Suppressing weeds naturally (saving us all from that endless weeding!)
• Filling spaces between larger shrubs and roses

We've always enjoyed its slightly sprawling habit as it weaves through borders, creating a natural, flowing appearance rather than something that looks too rigid or formal. The deeply divided, mid-green foliage provides a lovely backdrop for the flowers and maintains interest even when the plant isn't in bloom.

Award-winning Status (RHS AGM)

It comes as no surprise to us that Geranium 'Johnson's Blue' has been awarded the prestigious Royal Horticultural Society Award of Garden Merit (RHS AGM). Having exhibited at RHS shows, we know this distinction isn't given lightly - it represents careful research and evaluation by RHS experts.

For a plant to receive this honour, it must demonstrate outstanding qualities including being excellent for ordinary garden conditions, having good constitution, not requiring specialist growing conditions, showing resistance to pests and diseases, remaining stable in form and colour, and being reasonably available to purchase.

This recognition really does reflect what those of us who grow these plants have known for years - this variety is vigorous, versatile and exceptionally easy to grow. If you're looking for a tried and tested performer for your garden, the AGM status gives you that extra reassurance that this plant has been thoroughly put through its paces and will perform admirably in UK gardens.

Ideal Growing Conditions for Success

After many years of growing Geranium Johnson's Blue here at the nursery, we've found that while it's certainly a forgiving plant, getting those growing conditions spot on will reward you with the most spectacular display. It's rather like having a good friend to stay - they'll be perfectly happy with the basics, but they'll absolutely flourish if you give them exactly what they love!

Sunlight and Aspect Preferences

In our experience, Geranium Johnson's Blue performs best with 6-8 hours of direct sunlight daily. That said, one of the things we adore about this versatile plant is how it accommodates various garden positions. We have it growing in both full sun and dappled shade areas of our nursery, and it copes admirably in both situations.

What's particularly impressive is that this adaptable geranium really isn't fussy about aspect. We've seen it flourishing in the east, south, west, and even north-facing positions in our customers' gardens. This flexibility means you can place it almost anywhere with confidence. If you're gardening in a particularly hot area (we certainly don't have that problem here in Lincolnshire!), we'd suggest morning sun with afternoon shade provides the ideal balance, protecting the plant from scorching while ensuring sufficient light for those vibrant blue flowers.

Soil Types and Drainage Needs

One of Johnson's Blue's greatest strengths is its soil adaptability. This accommodating plant grows successfully in:

• Chalk
• Clay
• Loam
• Sand

Despite this versatility, proper drainage remains essential - the one soil condition this geranium simply won't tolerate is waterlogging. We learned this lesson when we had those terribly wet winters! For optimal results, aim for moderately fertile, moist but well-drained soil.

When we're planting at the nursery, we always incorporate plenty of organic matter such as compost or well-rotted manure. This improves soil structure, enhances drainage in heavy soils, and increases moisture retention in sandy soils. It's a bit like giving your plants a good breakfast before asking them to perform - they'll manage without it, but they'll do so much better with that extra boost!

Watering and Feeding Tips

Although reasonably drought-tolerant once established, Geranium Johnson's Blue benefits from consistent moisture. We water regularly during dry spells, paying special attention to newly planted specimens. A good rule of thumb we follow is to water when the top 1-2 inches of soil feels dry.

We are a great believer in mulching - we apply a generous 5-7cm layer of well-rotted manure or garden compost around our plants. This helps retain moisture, suppresses those pesky weeds, and gradually feeds the soil as it breaks down.

For feeding, we apply a balanced fertiliser every 4-6 weeks during the growing season. This supports robust growth and ensures those prolific flowers that Johnson's Blue is celebrated for.

Caring for Your Geranium Johnson's Blue Throughout the Seasons

Looking after your Geranium Johnson's Blue couldn't be simpler, which is why we are such a fan of this particular variety. Over the years at the nursery, we've found that this low-maintenance perennial responds brilliantly to just a few basic care techniques that keep it looking absolutely splendid year after year.

The Chelsea Chop - Well, Sort Of!

The most important maintenance job with Johnson's Blue is getting your timing right with cutting back. We always tell our customers that this single job makes all the difference to the plant's performance. Once the initial flush of flowers starts to fade in July, we grab my secateurs and cut back the entire plant by roughly a third. This might seem drastic if you haven't done it before but - trust me - the plant absolutely loves it!

For those feeling a bit braver (or if your plants are looking particularly tired), you can be even more ruthless and cut the flowered stems and old leaves right back to the base. We've done this countless times at the nursery, and the plants always bounce back with fresh foliage and often a lovely second display of those beautiful blue flowers.

Don't forget to tidy up any browned foliage before spring arrives, too. Not only does this keep everything looking neat, but it also helps reduce the risk of any diseases taking hold over winter.

Keeping Pests and Diseases at Bay

While Johnson's Blue is generally a robust plant, we do occasionally encounter a few troublemakers at the nursery:

• Pests: Keep an eye out for vine weevils, sawflies, capsid bugs, spider mites and those pesky aphids. These little blighters can cause distorted growth and weakened plants. We make a habit of regularly checking the undersides of leaves where many pests like to hide. One of the joys of our organic approach at the nursery is encouraging natural predators - we find ladybirds are particularly helpful allies against aphid problems.

• Diseases: Like many hardy geraniums, Johnson's Blue can sometimes suffer from powdery mildew (particularly during dry spells), downy mildew and occasionally rust. We've found that ensuring good air circulation, spacing plants properly, and avoiding overhead watering are the best preventative measures against these fungal issues.

The good news is that geraniums rarely attract the attention of rabbits, and even slugs and snails usually head for tastier treats elsewhere in the garden. That's certainly a bonus for those of us who prefer to garden without chemicals! 

Creating More Plants - Division and Cuttings

One of the things we love most about Johnson's Blue is how easy it is to propagate. Division is by far the simplest method - we tend to divide established clumps either in early spring or autumn when the soil is nice and moist. Simply lift the plant carefully, tease the root ball into sections (making sure each piece has both roots and foliage), and replant straight away.

This not only gives you new plants for free but also rejuvenates older, overcrowded specimens. At the nursery, we've found that plants that have been divided flower much more prolifically than those left to their own devices for too long.

For those wanting to try something different, basal cuttings taken in early to mid-spring work well too. Select healthy, non-flowering stems about 10-15 cm long, remove the lower leaves, and plant directly into a free-draining potting mix. While some gardening books suggest rooting cuttings in water first, we've had much better success rates rooting them directly in compost.

We always try to divide my Johnson's Blue plants every three to four years to keep them vigorous and flowering abundantly. It's such a simple job but makes such a difference to their performance.

Where and How to Use it in Your Garden

Geranium Johnson's Blue is one of those wonderfully versatile plants that we find ourselves recommending time and again to visitors at our nursery. Its adaptability means it slots beautifully into almost any garden setting, making it perfect for both gardening beginners and those of us who've been getting our hands dirty for decades!

Perfect for a Cottage and Informal Borders

We've always thought that Johnson's Blue creates that lovely, relaxed look that's so essential to a proper cottage garden. The way it slightly sprawls and weaves through borders gives that soft, billowy effect that's impossible to achieve with more rigid plants. When we are designing borders for customers, we often suggest planting in generous drifts of three, five, or seven plants, depending on the space available.

There's something rather magical about seeing sweeping waves of that beautiful blue spreading through a garden. Last summer, we planted a client's border with Johnson's Blue alongside traditional cottage garden classics like foxgloves and coreopsis. The combination was absolutely stunning! Those lavender-blue flowers brought such depth to the planting scheme, creating that quintessentially English garden feel that so many of us strive for.

Great Companion for Roses and Shrubs

One of my favourite ways to use Johnson's Blue is tucked around the base of roses and shrubs. Its dense growth creates this attractive foundation that really enhances taller plants. We've found that the blue flowers provide the most wonderful contrast to pink roses - the combination is simply harmonious.

Over the years, we've experimented with various companion plantings. Our personal favourites include:

• Purple Heuchera - the contrasting foliage colour creates a striking combination
• Slender grasses like Stipa tenuissima - the different textures play off each other beautifully
• Nepeta - they enjoy similar growing conditions, and the complementary blue tones are a dream together
• Salvia - they have compatible watering needs and the vertical accent of Salvia works brilliantly with the more spreading habit of Johnson's Blue

Ground Cover and Edging Uses

We've come to particularly appreciate Johnson's Blue for its ground cover abilities. Thanks to its rhizomatous growth habit, it forms these wonderful dense hummocks that suppress weeds naturally. Given a bit of time, it can easily reach widths of 0.5-1m over several years, making it perfect for covering bare soil between larger plants or along the front edges of borders.

At our own garden, we've used Johnson's Blue as an edging plant, allowing it to spill gently over the path edges. Its compact height combined with that generous spread makes it perfectly proportioned for softening hard landscape features. The effect is both practical and beautiful - exactly what we're after in the garden!

Seasonal Interest from Spring to Autumn

What we particularly love about Johnson's Blue is how hard it works throughout the seasons. In good years at our nursery, we see the first flowers appear in early May and continue well into mid-autumn. Then, as temperatures cool, the foliage transforms into these vibrant shades of red and gold, creating a stunning autumn display.

This long-season appeal makes it such a valuable garden workhorse. There are precious few plants that provide this level of consistent colour and structure throughout most of the growing season. It's this extended period of interest that makes Johnson's Blue worth its weight in gold in our garden design toolkit.

Conclusion

Well, what can we say about Geranium Johnson's Blue that we haven't already shared? It's quite simply one of those plants that deserves a special place in any garden. We've grown this lovely perennial for years now, and its combination of stunning blue flowers, adaptable nature, and multiple uses in the garden continues to impress me season after season.

The fact that it holds the prestigious RHS Award of Garden Merit speaks volumes, doesn't it? This isn't an accolade handed out lightly, and it confirms what so many UK gardeners already know - this plant truly delivers reliable performance with minimal fuss.

We remember visiting a garden in Lincolnshire last autumn where the Johnson's Blue had turned the most magnificent copper-red colour - it was absolutely breathtaking against the low October sun.

For busy gardeners (and who isn't these days?), the straightforward maintenance is another huge plus. That simple cut-back after the initial flowering flush makes such a difference - rejuvenating both foliage and blooms. And while we do recommend dividing clumps every three to four years to maintain vigour, it's hardly a demanding task compared to the rewards you'll receive.

We genuinely believe that Geranium Johnson's Blue represents excellent value for your garden. Its true blue flowers are a rare treasure, its adaptable nature suits both novice and experienced gardeners, and its low-maintenance requirements fit perfectly into today's busy lifestyles. It might just be that missing piece that transforms your garden from pleasant to truly spectacular.

When customers visit our nursery asking for a reliable, beautiful perennial that "just works," Johnson's Blue is invariably one of our first recommendations. Nine times out of ten, they come back the following year looking for more! 

Frequently Asked Questions about Geranium 'Johnson's Blue'

What makes Geranium 'Johnson's Blue' a standout choice for gardens?

Geranium 'Johnson's Blue' is renowned for its vibrant lavender-blue flowers, compact growth habit, and ability to form dense ground cover. It has received the RHS Award of Garden Merit, confirming its excellent performance in UK gardens.

When is the best time to plant Geranium 'Johnson's Blue'?

Geranium 'Johnson's Blue' can be planted throughout the year, as long as the ground isn't frozen. Its well-developed root system allows for successful establishment in various seasons.

How should I care for Geranium 'Johnson's Blue' to ensure optimal growth?

Provide 6-8 hours of sunlight daily, plant in well-draining soil, and water regularly during dry spells. Cut back after the initial flowering to encourage a second bloom and divide every 3-4 years to maintain vigour.

What are some effective ways to use Geranium 'Johnson's Blue' in garden design?

 Geranium 'Johnson's Blue' is versatile and can be used in cottage gardens, as underplanting for roses and shrubs, as ground cover, or for edging paths. It pairs well with plants like purple Heuchera, Stipa tenuissima, and Nepeta.

How long does Geranium 'Johnson's Blue' provide garden interest?

Geranium 'Johnson's Blue' offers extended seasonal interest, typically flowering from early May well into mid-autumn. In addition to its long blooming period, its foliage turns vibrant shades of red and gold in autumn, providing visual appeal for most of the growing season.

Can Geranium ‘Johnson’s Blue’ grow in partial or light shade?

Yes, Geranium ‘Johnson’s Blue’ is remarkably adaptable and performs well in both full sun and partial shade. While it produces the most abundant clusters of lavender-blue flowers in full sun, it still thrives and blooms reliably in light shade, making it ideal for borders with varied light conditions.

How quickly does Geranium ‘Johnson’s Blue’ grow and spread?

The rate of growth is moderate to fast. Once established, this outdoor plant forms a dense mound of foliage within a single season and can spread up to 75cm wide. It’s ideal for quickly covering bare soil and suppressing weeds.

What should I do to encourage fresh growth after flowering?

To promote fresh growth and potentially a second wave of blooms, cut the plant back by about a third after the initial flowering flush in early summer. This rejuvenates the foliage and often leads to a new round of flowering later in the season.

Is Geranium ‘Johnson’s Blue’ suitable for gardens in dry weather conditions?

Once established, Johnson’s Blue is fairly drought-tolerant and copes well in dry weather. However, like most perennials, it performs best with regular watering during prolonged dry spells, especially during its flowering phase.

Does Geranium ‘Johnson’s Blue’ offer continuous blooming?

Although not technically continuous, this geranium is a prolific bloomer. It flowers from late spring to mid-summer, and with a mid-season cutback, it often produces a second flush, extending its blooming season well into autumn.

Will Geranium ‘Johnson’s Blue’ flower well in outdoor pots or containers?

While primarily grown as a border or ground cover plant, Johnson’s Blue can be used in large outdoor containers with good drainage. Make sure the pot gets plenty of sun or partial shade and maintain regular watering, especially in dry weather.

How does the plant produce its clusters of lavender blooms so reliably?

Geranium ‘Johnson’s Blue’ is a sterile hybrid, which means it doesn’t divert energy into seed production. Instead, it puts its resources into continuous blooming, resulting in plentiful clusters of lavender-blue flowers throughout summer.

Is this geranium a good choice for low-maintenance outdoor plants?

Absolutely. Its resilience, pest resistance, and self-sufficiency once established make Geranium ‘Johnson’s Blue’ one of the best low-maintenance outdoor plants. With just a seasonal cutback and occasional watering, it reliably rewards you with colour and structure year after year.