Petunia

Spring-Autumn · Outdoors

Water during dry periods

For plants in the ground, when there has been little or no rain for a period of 7-10 days and the soil is dry, give it a deep watering and repeat weekly until there is a downpour of rain. Check plants in pots more frequently, especially in hot weather.

Spring-Autumn · Outdoors

Feed with high potash feed several times

Apply a fertiliser that is high in potash (potassium) several times while the plant is in flower.

Where fertiliser values are listed on a packet they are in order - nitrogen, phosphate, potassium with percentage values of each. For high potash choose a fertiliser where potassium is higher.

Spring-Autumn · Planting

Protect from slugs & snails

Protect young plants and new growth from slugs; mature plants can withstand slugs though damage affects their appearance. Apply nematodes in Spring. Or sprinkle organic slug pellets thinly around plants. Barrier methods, eg copper tape, may help.

Winter-Spring · Planting

Protect from winter cold

Bring the plant into a frost-free area before frosts occur, and do not put them outside until all danger of frost is past. Follow watering instructions, or allow the plant a period of dormancy during the winter.

Plants need to be brought inside in cold areas, i.e. colder than zone 8.

Planting

Deadhead blooms during flowering season

Remove flowers as they turn brown and fade. Snip the stem just below the bloom. This will keep the plant tidy and encourage more flowers.

The removal of spent flowers encourages the plant to produce fresh ones, rather than spend its energy on the development of seeds.

Compost · Planting

Loam based compost + grit for repotting

Use a free draining loam based compost rather than one which has been modified to be 'moisture retentive'.

Alternatively prepare a compost using three parts of loam (John Innes no. 2 or 3) to one part of (horticultural) sand or fine (horticultural) grit.

Compost · Planting

Multi-purpose compost

Use a good quality peat-free multi-purpose compost when growing in pots and containers.