As a lifelong gardener, I’ve grown countless perennials over the years. But few have captured my heart quite like Geranium ‘Azure Rush’. This stunning hardy geranium produces masses of sky-blue flowers that float above mounding foliage from late spring through fall. If you’re looking to add season-long color and charm to your garden, Azure Rush is hard to beat.
I’ve been growing Azure Rush in my own garden for the past five years and have picked up plenty of tips and tricks along the way. In this guide, I’ll share everything I’ve learned about cultivating this garden superstar. We’ll cover ideal growing conditions, planting techniques, care and maintenance, and creative ways to use Azure Rush in your landscape design. By the end, you’ll have all the knowledge you need to successfully grow this beautiful perennial.
About Geranium ‘Azure Rush’
Before we dive into the nitty-gritty of growing Azure Rush, let’s take a closer look at what makes this plant so special:
- Botanical name: Geranium ‘Azure Rush’
- Common names: Azure Rush cranesbill, Azure Rush hardy geranium
- Plant type: Herbaceous perennial
- Mature size: 18-24 inches tall and 24-36 inches wide
- Bloom time: Late spring to fall
- Flower color: Pale blue with darker veining
- Foliage: Mounding, deeply lobed green leaves
- Hardiness zones: USDA zones 5-9
Azure Rush is a relatively new variety, introduced in 2005 as an improved cultivar of the popular Geranium ‘Rozanne’. It shares many of Rozanne’s desirable traits but with a more compact growth habit and slightly lighter blue flowers. The long bloom period and easygoing nature of Azure Rush have made it a fast favorite among gardeners.
Choosing the Perfect Spot
Like many perennials, Azure Rush thrives when given the right growing conditions. Here’s what to look for when selecting a planting site:
Sunlight Requirements
In my experience, Azure Rush performs best with full sun to partial shade. I’ve found it blooms most prolifically when given at least 6 hours of direct sunlight daily. However, in hotter climates, some afternoon shade can prevent scorching and keep the plant looking fresh.
My Azure Rush plants growing in dappled shade under a large maple tree still bloom well, albeit not quite as heavily as those in full sun. The shade-grown plants tend to have a looser, more open growth habit too.
Soil Type and Drainage
When it comes to soil, Azure Rush isn’t overly fussy. It grows happily in average garden soil as long as it’s well-draining. I’ve had success growing it in both clay and sandy soils after amending with compost.
The key is ensuring the soil doesn’t stay waterlogged. Azure Rush won’t tolerate wet feet, so avoid low spots where water collects. If your soil is heavy clay, consider planting on a slight mound or in raised beds to improve drainage.
Climate Considerations
Azure Rush is fairly adaptable when it comes to climate. It’s hardy in USDA zones 5-9, meaning it can withstand winter temperatures down to about -20°F (-28°C). In colder zones, a layer of mulch over the crown in winter can provide extra protection.
In my zone 6 garden, Azure Rush sails through our cold winters without any special care. It’s also proven remarkably heat tolerant, continuing to bloom even during our humid summer heat waves.
Planting Your Azure Rush
Once you’ve selected the perfect spot, it’s time to get planting. Here’s my step-by-step process for giving Azure Rush a strong start:
When to Plant
The best time to plant Azure Rush is in spring or early fall. This gives the plants time to establish a strong root system before the extremes of summer heat or winter cold.
I prefer planting in early spring, just as new growth is emerging. This allows me to enjoy a full season of blooms in the first year. Fall planting works well too, but you may not see much top growth until the following spring.
Preparing the Soil
Before planting, I always take the time to prepare the soil properly. Here’s my process:
- Remove any weeds or grass from the planting area.
- Loosen the soil to a depth of about 12 inches using a garden fork or tiller.
- Mix in 2-3 inches of compost or well-rotted manure. This improves both drainage and fertility.
- Rake the area smooth.
Planting Technique
When you’re ready to plant, follow these steps:
- Dig a hole twice as wide as the root ball and just as deep.
- Gently remove the plant from its container and loosen any circling roots.
- Place the plant in the hole, making sure the top of the root ball is level with the soil surface.
- Backfill with soil, firming gently to eliminate air pockets.
- Water thoroughly to settle the soil around the roots.
Space multiple plants about 18-24 inches apart to allow room for their mature spread. I like to plant Azure Rush in groups of three or five for a fuller, more naturalistic look.
Caring for Your Azure Rush
Once established, Azure Rush is a relatively low-maintenance plant. However, a little TLC will keep it looking its best and blooming prolifically. Here’s my care routine:
Watering
Azure Rush has average water needs. I water deeply once a week during dry spells, making sure the soil stays evenly moist but not waterlogged. Once established, it’s quite drought tolerant and can go longer between waterings.
In particularly hot or dry weather, I’ll give my plants an extra drink if I notice wilting. Mulching around the base of the plants helps retain moisture and reduce watering needs.
Fertilizing
Azure Rush isn’t a heavy feeder, but it appreciates a little nutrition boost. I apply a balanced, slow-release fertilizer in early spring when new growth emerges. A light application of compost or well-rotted manure around the plants in spring or fall also helps keep them vigorous.
Avoid over-fertilizing, especially with high-nitrogen fertilizers. This can lead to lush foliage at the expense of flowers.
Pruning and Deadheading
One of the great things about Azure Rush is its long bloom time. To keep the flowers coming, I deadhead spent blooms regularly. Simply pinch off the faded flowers with your fingers or snip them with scissors.
In midsummer, if the plants are looking a bit tired or leggy, I give them a light shearing. This rejuvenates the foliage and often triggers a fresh flush of blooms.
Winter Care
In most areas, Azure Rush doesn’t need much winter protection. I leave the foliage in place over winter to protect the crown. In spring, I cut back any remaining dead foliage to make way for new growth.
In colder zones, you might want to apply a layer of mulch around the base of the plants after the ground freezes. This helps prevent frost heaving.
Propagation
Want more Azure Rush plants? Good news – they’re easy to propagate! Here are two methods I’ve had success with:
Division
Every 3-4 years, I divide my Azure Rush plants to keep them vigorous and create new plants. Here’s how:
- In early spring, dig up the entire plant.
- Using a sharp spade or knife, cut the rootball into 2-3 sections, making sure each has plenty of roots and some top growth.
- Replant the divisions at the same depth they were growing before.
- Water well and keep moist until new growth appears.
Cuttings
You can also propagate Azure Rush from stem cuttings:
- In early summer, take 3-4 inch cuttings from non-flowering stems.
- Remove the lower leaves, leaving just 2-3 sets at the top.
- Dip the cut end in rooting hormone.
- Plant in a pot filled with moist potting mix.
- Keep in a bright, warm spot out of direct sun until roots form (usually 3-4 weeks).
Pest and Disease Problems
In my experience, Azure Rush is a pretty tough plant. I’ve had very few issues with pests or diseases. However, there are a few potential problems to watch out for:
Pests
- Slugs and snails: These can damage young foliage. I use iron phosphate pellets or beer traps to control them.
- Vine weevils: The larvae can damage roots. Beneficial nematodes can help control them.
Diseases
- Powdery mildew: This can occur in humid conditions or with poor air circulation. I prevent it by spacing plants properly and avoiding overhead watering.
- Root rot: This is usually caused by overwatering or poor drainage. Make sure your soil drains well and don’t overwater.
Landscape Uses for Azure Rush
The versatility of Azure Rush makes it a valuable addition to many garden styles. Here are some of my favorite ways to use it:
- Front of the border: Its compact habit makes it perfect for edging paths or the front of perennial borders.
- Rock gardens: Azure Rush thrives in the well-draining conditions of rock gardens.
- Container plantings: It makes a stunning centerpiece in pots or window boxes.
- Ground cover: Mass plantings create a beautiful carpet of blue flowers.
- Cottage gardens: The informal, billowing habit fits perfectly in cottage-style plantings.
I particularly love pairing Azure Rush with plants that have contrasting foliage or flower colors. Some great companions include:
- Heuchera ‘Caramel’ for its coppery foliage
- Rudbeckia ‘Goldstrum’ for a classic blue and yellow combination
- Nepeta ‘Walker’s Low’ for a soothing blue-on-blue effect
- Sedum ‘Autumn Joy’ for late-season interest
Wrapping Up
Geranium ‘Azure Rush’ is a true garden workhorse, offering months of beautiful blue blooms with minimal fuss. Whether you’re a seasoned gardener or just starting out, this hardy geranium is sure to become a favorite in your landscape.
Remember, the key to success with Azure Rush is well-draining soil, plenty of sunlight, and regular deadheading. With these basics covered, you’ll be rewarded with a stunning display of sky-blue flowers from late spring right through to the first frosts of fall.
So why not give Azure Rush a try in your garden this year? I promise you won’t be disappointed. Happy gardening!