Growing Capsicums

Capsicums grow well in Sydney’s temperate zone and love the sunny spots in your garden. They need a long growing season so if you want to harvest your own sweet, tender fruits there is still just enough time to plant out some capsicum seedlings.

Growth habits and planting needs

Capsicums like a sunny position in full sun. The best way to propagate them is from seed but they can be transplanted as seedlings if great care is taken.

Choose the location well. It should be sunny and open with good airflow to prevent fungal diseases. It should also have protection from winds that may damage the plants.

Capsicums should follow leaf crops that are heavy feeders of nitrogen, in the crop rotation system. As fruiting crops, they need potassium to set flowers but if there is too much nitrogen in the soil they will make leaf growth at the expense of fruit. The soil will have been depleted of excess nitrogen after the leaf crop.

Prepare the soil well by digging in well rotted compost to a depth of of 60 cm paying atention to removing clods. As capsicums have an extensive root system and a long tap root that can grow to 1 m, the soil should be deep, at least 30 cm, be friable and have good drainage. They prefer a pH of 5.0- 6.0.

Plant in September after the final frost when soil temperature is between 18 C and 35 C, in late spring.

Soak the seeds in water for 8-24 hours until the seeds sink to the bottom of the container.

Planting direct into the final position, once the soil is warm enough has the advantage of avoiding transplant shock. This method of planting will require extra effort but the seedlings will be hardy because the root system is not disturbed.

Make raised mounds that are finely tilled and plant some seeds in each. Sow thinly 5mm deep and cover with fine layer of seed raising mix, watering with a fine mist of diluted sea weed solution. Keep moist but not overly wet so seeds do not rot. The seedlings should emerge in 10-14 days.

Thin out the weaker growths when they are about 4-5 cm tall by cutting with small scissors just below the surface.

To ensure good size fruit space the seedlings 50-60 cm apart and spacing rows 1 m apart. Closer spacing will mean smaller fruit.

Capsicum root system — The root system of the nearly mature capsicum. Source: Soil and Health Library, J.E.Weaver and W.E.Bruner (grid measure in ft)

Capsicums have an extensive system of roots close to the surface spreading 45 cm around each plant and reaching down 1 m and so it is essential to keep weeding to a minimum to avoid disturbing this root system. The best way is to place a good layer of mulch around the plants, keeping it away from the main stem.

Water fortnightly with a diluted seaweed solution watering the plants from below to prevent fungal diseases.

As the fruit matures stake the plants to support them

Harvesting

The capsicum fruits will mature in 18 – 20 weeks. They will be sweeter if picked when red or yellow but they may be harvested when green too if desired.

By picking the fruits as they reach maturity the plants will continue to bear new fruit over the summer.