Colorful summer gardens aren’t complete without these classic blooms that bring charm to any outdoor space. Growing these flowers successfully requires a blend of the right conditions, timing, and care techniques that many gardeners overlook.
Last summer, I tried something new with spacing, and it actually made a huge difference in how my flower beds performed. The results were so impressive that my neighbors started asking for advice on their own garden patches.
Whether you’re planting them in borders, hanging baskets, or creating a sprawling field of color, these tips will help you achieve the garden of your dreams. With a few adjustments to your routine, you’ll be amazed at how these flowering plants respond.
1. Choose The Right Varieties
Modern hybrids offer incredible advantages over older types. Wave petunias spread beautifully without pinching, while multiflora varieties produce smaller but more abundant blooms that withstand rain better.
I used to stick with the same basic varieties until a gardening friend introduced me to the Supertunia series. The difference in performance was immediately noticeable – they barely needed deadheading and flowered until the first frost.
For large fields, mixing spreading types with upright varieties creates a tapestry effect with different heights and growth habits that looks natural and requires less maintenance.
2. Start Seeds At The Perfect Time
Timing makes all the difference when growing from seed. Begin the process 8-10 weeks before your last expected frost date for healthy, robust transplants when planting time arrives.
Seeds need light to germinate, so press them gently onto the soil surface rather than burying them. My first attempt failed because I covered the tiny seeds with too much soil – they simply couldn’t push through.
Keep seedling trays consistently moist with a fine mist sprayer and maintain temperatures between 70-75°F for optimal germination. A heat mat underneath seed trays can dramatically improve your success rate.
3. Perfect Your Soil Preparation
Sandy loam with excellent drainage creates the ideal growing environment. Working in compost before planting improves both drainage and nutrient content – a winning combination for root development.
Raised beds work wonders for areas with heavy clay soil. I built mine just 8 inches high, but the difference in plant health compared to my in-ground beds was remarkable. The plants established faster and grew more vigorously throughout the season.
Aim for a slightly acidic pH between 6.0 and 6.5 for best results. A simple soil test kit from your local garden center will help you make any necessary adjustments before planting.
4. Space Plants Strategically
Proper spacing prevents disease problems while creating a lush field effect. Standard varieties need 12 inches between plants, while spreading types require 18-24 inches to reach their full potential.
Staggered planting patterns (think diamond formation rather than grid lines) create a more natural-looking display. This approach also maximizes your growing area without crowding individual plants.
I used to crowd mine in because I didn’t want to waste space—turns out they hate that. When I finally gave them room to breathe, they rewarded me with nearly double the flowers and much healthier foliage throughout the season.
5. Master The Watering Schedule
Deep, infrequent watering encourages strong root systems that can withstand summer heat. Aim for about an inch of water weekly, adjusting for rainfall and temperature conditions in your area.
Morning watering reduces fungal disease risk by allowing foliage to dry completely before evening. Installing a simple drip irrigation system saves time and delivers water directly to the roots where it’s needed most.
Mulching around plants with a light layer of pine straw or fine bark helps maintain consistent soil moisture. Just keep the mulch from touching the stems directly to prevent rot issues that can quickly spread through your planting.
6. Fertilize For Continuous Blooms
Balanced feeding keeps flowers coming all season long. These plants are heavy feeders that benefit from regular fertilization with a bloom-boosting formula (higher phosphorus content).
Liquid fertilizers applied every two weeks provide immediate nutrients, while slow-release granules offer convenient long-term feeding. My breakthrough came when I started using a combination approach – slow-release at planting time supplemented with liquid feed during peak growing season.
Watch for yellowing lower leaves, which often signal nitrogen deficiency. A quick foliar spray with a diluted high-nitrogen fertilizer can green things up within days while your soil amendments take effect.
7. Deadhead Like A Professional
Regular deadheading redirects energy from seed production back to flower formation. For traditional varieties, pinch spent blooms just below the flower head where it meets the stem.
The “pinch and twist” technique works best – gently pinch the faded flower between your thumb and forefinger, then twist to remove it cleanly. Carrying a small container while deadheading keeps your garden tidy and prevents diseases from spreading through fallen debris.
For larger plantings, try the “haircut method” every few weeks. Using clean garden shears, trim back about one-third of the plant’s height when blooming slows to stimulate fresh growth and a new flush of flowers.
8. Prevent Common Pests Naturally
Aphids and slugs frequently target tender growth. Introducing beneficial insects like ladybugs creates a natural defense system that keeps pest populations in check without chemicals.
A simple homemade spray of 1 tablespoon mild dish soap mixed with a quart of water effectively controls aphids without harming plants. Apply in the evening when beneficial insects are less active, focusing on leaf undersides where pests hide.
Copper tape barriers around beds deter slugs and snails effectively. I was skeptical until trying this method last season – the difference was remarkable, and I didn’t lose a single plant to slug damage for the first time ever.
9. Solve Disease Problems Early
Powdery mildew appears as white patches on leaves during humid periods. Improving air circulation by proper spacing and morning watering prevents most disease issues before they start.
Fungal problems respond well to neem oil treatments applied at the first sign of trouble. Mix 2 teaspoons of neem oil with a quart of water and a drop of mild dish soap, then spray weekly until symptoms disappear.
Remove and dispose of severely affected plants immediately to protect neighboring plants. This was hard for me to do initially – I wanted to save every plant – but I learned that sacrificing one or two early saves dozens more from infection.
10. Encourage Bushy Growth
Pinching young plants creates fuller, more floriferous specimens. When seedlings reach 4-6 inches tall, remove the growing tip to encourage branching from the base.
Regular trimming throughout the season maintains shape and vigor. Every few weeks, trim back any leggy stems by about one-third their length to keep plants compact and stimulate new flowering branches.
Avoid the common mistake of fertilizing stressed or leggy plants without pruning first. The first year I grew a large planting, I tried to fix legginess with extra fertilizer – it only made the problem worse until I learned to prune before feeding.
11. Create Stunning Color Combinations
Monochromatic schemes using different shades of the same color create sophisticated, cohesive displays. Purple and white varieties planted together create a particularly striking contrast that’s visible from a distance.
Color blocking – planting distinct sections of single colors – creates a dramatic patchwork effect in larger areas. This approach works beautifully in fields where you want to create patterns or visual interest from viewing points.
Consider bloom times when selecting varieties to ensure continuous color. My garden looked sparse in spots until I learned to combine early, mid, and late-season bloomers of similar colors for consistent coverage throughout the growing season.
12. Support Trailing Varieties Effectively
Cascading types need proper support to display their full beauty. Low decorative fencing provides both structure and visual interest while keeping plants from sprawling where they’re not wanted.
For steep slopes or retaining walls, install guidewires parallel to the ground at different heights. These nearly invisible supports prevent damage from heavy rain while maintaining a natural flowing appearance.
A row of strategically placed stones creates natural-looking “stops” that direct growth patterns. This technique transformed my sloped garden bed from a chaotic tangle to an artful cascade – the plants still flow beautifully but stay exactly where I want them.
13. Extend The Blooming Season
Selective pruning in midsummer rejuvenates tired plants for a second flush of blooms. Cut back about half the stems by one-third their length, leaving the rest intact to maintain some color while the pruned portions regrow.
Adjusting fertilizer formulations as the season progresses makes a noticeable difference. Switch from a balanced feed to a higher-phosphorus formula (like 5-10-5) in late summer to encourage maximum flower production rather than foliage growth.
Providing afternoon shade in the hottest regions extends flowering significantly. I use shade cloth that blocks 30% of sunlight during July and August – this simple addition gave me nearly a month of extra blooms compared to previous years.
14. Manage Weeds Without Chemicals
Landscape fabric beneath mulch creates an effective weed barrier while allowing water penetration. Cut X-shaped slits for planting, keeping them as small as possible to prevent weed seeds from finding openings.
Hand weeding regularly when weeds are tiny saves tremendous effort later. I set a timer for just 10 minutes of weeding each morning while enjoying my coffee – this small daily habit prevented the overwhelming weekend weeding sessions I used to dread.
Corn gluten meal applied in early spring works as a natural pre-emergent herbicide. It won’t kill existing weeds but prevents new seeds from establishing roots, significantly reducing weed pressure throughout the growing season.
15. Protect From Extreme Weather
Temporary row covers shield tender plants from late spring frosts or unexpected cold snaps. Keep the material on hand and drape it over plants when temperatures threaten to drop below 35°F, removing it promptly the next morning.
For hail protection in storm-prone areas, inexpensive plastic crates turned upside down work remarkably well. After losing half my planting to a surprise hailstorm, I started keeping these ready – they’ve saved my garden twice since then.
Windbreaks benefit exposed garden areas tremendously. Even temporary solutions like straw bales positioned strategically or lattice panels can prevent wind damage that stresses plants and reduces flowering.
16. Document Your Success
Garden journals help track what works and what doesn’t from season to season. Record planting dates, varieties, weather conditions, and any treatments applied to build a personalized growing guide for your specific location.
Take weekly photos from the same vantage points to create a visual record of growth patterns. These images provide invaluable information about spacing effectiveness and bloom progression that memory alone can’t capture accurately.
Soil test results tracked over multiple seasons reveal improvement patterns that inform future amendments. My notes from three years ago showed severe phosphorus deficiency – comparing those results with current tests confirms my amendment strategy is working.