For a border that carries colour from spring to autumn, a sequence of well-chosen annuals works better than one oversized planting. Each group handles a different stretch of the season, and regular maintenance keeps the gaps from becoming obvious.
Although Angelo Bernacchi Greenhouse is rooted in LaPorte, Indiana, this guide focuses on Australian conditions. Its century-long tradition of quality and attentive service is reflected here in a straightforward aim: choose healthy plants, place them intelligently and maintain them consistently.
Australian conditions vary considerably. Sydney generally enjoys a long, mostly frost-free growing season, while Melbourne often brings cool spring mornings followed by sudden warm spells. Brisbane combines humidity with intense summer heat, so the same plant list cannot suit every garden.
Use plants sold by reputable Australian nurseries and read the maturity, spacing and sun labels rather than relying on a Northern Hemisphere calendar. Australia’s import and interstate biosecurity rules can restrict unapproved seed or plant material, making local suppliers the simplest starting point.
Separate cool-season annuals from warm-season performers. Sweet alyssum, lobelia and violas thrive in mild weather, while marigolds, angelonias and celosias provide stronger colour once temperatures rise. Planting both groups gives your beds overlapping flowering periods rather than a sharp change from spring favourites to summer plants.
Sun exposure matters as much as the variety. Petunias and marigolds generally perform best with at least six hours of direct light, while traditional impatiens and tuberous begonias appreciate filtered shade. In temperate Australia, a north-facing pot can receive gentle winter light but fierce summer sun, so afternoon shade may be needed.
Buy according to mature size and leave enough room for air to circulate. Crowded annuals dry unevenly and develop fungal problems more quickly, particularly during humid weather. A few centimetres of extra space around each plant can make a noticeable difference over an entire season.
Petunias and calibrachoa are dependable container performers, producing trailing colour for hanging baskets, window boxes and raised beds. Give them full sun, steady moisture and occasional light trimming. Plants that become stretched or untidy can be cut back by a third to encourage compact growth and fresh flowers.
For exposed borders, marigolds remain one of the most forgiving choices. French varieties suit bedding and containers, while taller African types make useful cut flowers. Angelonia handles heat well and rarely needs frequent deadheading; celosia adds upright plumes that contrast with rounded blooms. Regular removal of faded flower heads keeps all three producing at their best.
Pelargoniums bring long-lasting colour to sunny pots and edges. They tolerate short dry periods better than most bedding plants, although watering the soil rather than the foliage helps prevent fungal spots in humid districts. Trim tired stems after flowering, and replace plants that decline during extreme summer heat rather than keeping them in an unsuitable position.
One batch of seedlings rarely covers an entire growing season. Sow small quantities of petunias, calibrachoa and marigolds every three or four weeks so fresh plants replace tired ones gradually. Keep each batch in labelled containers until it is strong enough to harden off and transplant.
Use the sowing window on Australian seed packets, as Southern Hemisphere seasons differ from those printed on many imported guides. In cooler districts, autumn sowing produces spring flowers, while late-winter and spring sowing supports summer colour. In subtropical Brisbane, autumn is often the better starting point because mild conditions encourage establishment before the heat arrives.
For seed saved from open-pollinated varieties, an old secretary can provide compact storage; guidance on clearing old secretary compartments can help you assess small drawers before filling them with labelled packets. Store packets somewhere cool and dry, and remember that saved seed from hybrid plants may produce variable offspring.
Impatiens remain a reliable choice for moist, sheltered areas. Traditional bedding impatiens need more shade, whereas New Guinea varieties generally handle brighter positions and humid weather better. Check the soil before watering, as both types wilt dramatically when dry and struggle with constantly saturated soil.
Tuberous begonias provide large, shapely flowers in hanging baskets and pots under filtered light. They need well-drained compost, regular feeding and protection from heavy rain. Removing the first faded blooms encourages branching, while clear space around the plants improves airflow and reduces the risk of rot.
Torenia, blue lobelia and violas extend the flowering season in partly shaded containers. Hummingbirds do not live in Australia, but the habitat thinking behind hummingbirds and native perennials translates well: dependable nectar supplies support specialist pollinators. Grevillea, correa and other Australian natives can complement annual displays and keep flowers available beyond the bedding season.
Deadheading is one of the simplest ways to extend performance. Remove spent blooms before seeds form, particularly on petunias, begonias and marigolds. Use clean, sharp scissors and take the stem back to a healthy pair of leaves. Avoid cutting into bare, leggy growth where new shoots may not develop.
Water early in the morning so foliage dries before cool or humid evenings. Container displays can need checking daily during hot weather, yet frequent splashing still encourages disease. Apply a balanced slow-release fertiliser at the start of the main flowering period, then use a suitable liquid feed for containers that show weak growth or exhausted compost.
Finish with a mix of upright, rounded and trailing plants so the display retains interest between flowering peaks. Match each annual to its light and moisture needs, replace declining plants promptly and keep fresh growth coming. A steady, climate-matched planting that renews itself in waves delivers the most rewarding long season.