Domakihub How to Grow Petunias: Fuller Blooms All Season Long
Plant, feed, and deadhead your way to a cascade of colour on balconies, gardens, and terraces across Greece.
Reviewed by Domakihub garden pros · 2026-06-23 · 5 min read
Petunias are one of the hardest-working flowering annuals you can grow — their trumpet-shaped blooms fill pots, window boxes, and hanging baskets with colour from late spring right through to autumn. In Greece's warm, sunny climate they thrive with surprisingly little effort, making them a favourite for home gardens, holiday rental terraces, and hotel courtyards alike. The HGTV video above walks you through the planting essentials; this guide adds the full care routine so your petunias stay lush and generous all season.
Why Petunias Work So Well in Greece
Greece's combination of long sunny days, well-drained soils, and mild winters (in coastal and island areas) suits petunias almost perfectly. They prefer full sun — at least six hours a day — and tolerate summer heat as long as they are watered regularly and not left sitting in waterlogged compost. This makes them ideal for south- or west-facing balconies and terrace containers where other flowers would scorch.
For holiday rentals and hotels, petunias offer a practical bonus: they look welcoming and colourful in photographs without demanding daily attention from guests. A well-fed, deadheaded plant continues flowering even during a changeover between bookings.
Choosing the Right Variety
Petunia varieties fall into three broad groups. Grandifloras produce large individual blooms and suit sheltered spots; Multifloras give smaller but more numerous flowers and cope better with wind and rain; Wave or trailing types cascade over pot edges and are perfect for hanging baskets and window boxes on balconies. In Greece's dry Mediterranean summers, Multiflora and Wave types tend to be the most resilient choice for outdoor containers.
For a classic Greek terrace look, pair deep violet or cobalt blue petunias with white varieties — the colour palette echoes the Cycladic palette and photographs beautifully for rental listings.
How to Grow Petunias: 5 Key Steps
- 1
Choose the Right Pot and Position
Select a container at least 25–30 cm deep with drainage holes — petunias hate waterlogged roots. Place it in a spot that receives a minimum of six hours of direct sun each day. On shaded north-facing balconies, multiflora varieties are your best bet as they tolerate partial shade better than grandifloras.
- 2
Plant at the Right Time and Depth
In Greece, petunias can go outdoors from mid-March in the south and Aegean islands, and from early April in northern or higher-altitude areas, once night temperatures stay above 10 °C. Plant seedlings (or transplants from a nursery) at the same depth they sat in their original pot, spacing them 25–30 cm apart. Fill around them with quality multipurpose or potting compost mixed with a little perlite to improve drainage.
- 3
Water Consistently, Not Excessively
Petunias want moist but never soggy soil. During a Greek summer, container-grown petunias may need watering every day in July and August — check the top 2–3 cm of compost and water when it feels dry. Water at the base of the plant rather than over the flowers; wet petals are prone to botrytis mould in humid coastal areas. Install a drip irrigation timer if you manage a rental property remotely.
- 4
Feed Every Week with a High-Potassium Fertiliser
Heavy flowering depletes nutrients fast. Once petunias are established (about two weeks after planting), begin feeding them every seven to ten days with a liquid fertiliser high in potassium — tomato feed works well. This encourages continuous bud production rather than leafy growth. In pots, nutrients wash out with every watering, so consistent feeding is the single biggest factor separating sparse plants from lush, overflowing ones.
- 5
Deadhead and Cut Back for Continuous Blooms
Remove spent flowers regularly by pinching them off just below the dead bloom — this prevents the plant putting energy into seed production and triggers a fresh flush of buds. If your petunia becomes leggy mid-summer (long stems, few flowers), cut it back by one-third. Within two to three weeks it will bounce back bushier and more floriferous. This cut-back is especially useful in August before the autumn guest season at rental properties.
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FAQ
- Can petunias survive a Greek summer without shade?
- Yes — petunias are among the most sun-tolerant flowering annuals available. They actively prefer full sun and will bloom more prolifically in bright conditions than in shade. The key in high summer is to keep the watering consistent; a plant that wilts badly and repeatedly will drop flowers. If temperatures exceed 38 °C for several days in a row, moving pots to a spot with light afternoon shade can reduce stress without harming bloom production.
- How often should I replace petunias in rental property pots?
- Petunias are annuals, so plan to replant each spring. With good feeding and regular deadheading, a single planting in March or April should look presentable right through October. If a plant becomes too woody or stops flowering in late summer, a cut-back rather than a full replacement is usually enough to revive it for the autumn season.
- Why are my petunias leggy with few flowers?
- Legginess almost always comes from two causes: insufficient sun or insufficient feeding. Move the pot to a sunnier position if possible, begin weekly high-potassium liquid feeding, and cut the stems back by about a third. The combination of hard pruning plus consistent fertiliser will produce a bushier, more floriferous plant within three weeks. Also check that the pot is large enough — overcrowded roots in a small container restrict growth and flower production.