Growing and Using Chillies

Growing and collecting chillies has become a growing trend in WA. Where once the only chillies available on the market were either hot or mild, now we have the opportunity to grow bushes offering a range of heat, flavours, colours and shapes. They are well suited to growing in most regions of WA where there is strong summer sun and heat.

Chillies (Capsicum frutescens) originated from South and Central America where the temperatures are very warm and this helps them to produce good levels of ‘capsaicin’, the chemical that gives the fruit its heat. The more capsaicin present in the fruit, the fierier the fruit will be.

Often their true flavour is not fully appreciated due to their intense heat. Chilli have flavours ranging from nutty through smoky to fruity so selecting a chilli with a heat level that suits the palette is essential to taste the true flavour of this remarkable fruit.

Although they are short lived perennials in subtropical and tropical areas, in cooler regions of WA they should be treated as annuals with new bushes being planted each spring.

Once chilli bushes begin to produce fruit in December they will continue to be productive for many months, often well into April. It is best to harvest them often as this will encourage new fruit to be produced. In most cases, chillies mature from green through to red and occasionally black/purple and they can be picked at any stage along the way. Keep some of the stalk on the fruit to help when storing them. To dry chillies, simply tie them together and hang them in a dry area. They will shrivel up and then can be crushed to add into cooking.

Chilli can be mildly addictive and over time, regular chilli eaters can develop a tolerance to their heat levels which is fortunate for those that aspire to be a “Habanero Master”.

GROWING CHILLIES
Start with a site that’s in full sun or at least receives six hours throughout the day. It is the sun that will ensure healthy bushes with fruit that has the best flavour.

Chillies must have well-drained soil with a pH between 6 and 7 so they should be planted in an area enriched with either conditioned poultry mix or compost. Regular doses of low nitrogen liquid fertiliser applied once established will encourage fruiting and fortnightly applications of seaweed extract will ensure that the root systems are strong. The soil should be kept continuously moist to stop the flowers and young fruit from dropping so plenty of mulch and a trickle irrigation system throughout the drier months of summer is ideal.

Growing chillies in pots is a wonderful way to decorate the patio or barbecue area, especially when the bush is festooned with green and red fruit. Choose large containers which allow the roots to establish and to offer plenty of nutrients as this will ensure healthy growth and plenty of fruit. Fill the pot with premium quality potting mix which will have plenty of fertiliser as well as a wetting agent added already and sprinkle in some water saving crystals which will help to keep the soil moist.

To find out how to grow chillies from seed, check out the“Make New Plants by Seeding” factsheet on our website. The best time to plant chilli seed will be the end of August through to the beginning of October.

The optimum daytime temperature for fruit setting on a chilli bush is between 24 and 30 degrees C, right in the middle of our summer months so planting seedlings around spring will ensure that they are mature enough to fruit when the temperatures are perfect. Chillies do not generally require pruning or support except to help prevent damage from strong winds.

CHILLI HEAT SCALE
The heat of chillies is rated using Scoville Units, which is a scale developed by Wilbur Scoville in 1912 to measure capsaicin levels. The greater the number of Scoville Units the hotter the chilli. The hottest pepper recorded was a Habenero at 667,000 Scoville Units! The heat rating of 1 to 10 seen on plant labels is a simpler version and will give a good indication when purchasing plants.

SCOVILLE HEAT UNITS (SHU)
0 Capsicum, Pimento, Sweet Banana
500 to 1000 New mexica, Cherry,
1000 to 1500 Pasilla, Espanola, Anaheim
1500 to 2500 Sandia, Cascabel, Pasilla, Hot Cherry
2500 to 5000 Cayenne, Hungarian Wax
5000 to 15000 Serrano, Jalapeno, Aji Amarillo
15000 to 30000 De arbol, Japonese
30000 to 50000 Piquin, Cayenne Long Thin, Tabasco
50000 to 100000 Thai, Chiltepin, Santaka,
100000 to 300000 Habanero, Birdseye, Scotch Bonnet

TOO HOT TO HANDLE!
If you bite into chilli-laden food that causes the mouth to burn, don’t immediately reach for water to try to ease it. This will make the pain worse as the oily capsaicin within the fruit will be insoluble to the water and will spread more throughout the mouth. The most soothing option is to drink milk or eat bread or rice which will absorb the capsaicin and bring some relief.

Chillies should be handled with gloves as the capsaicin can be very painful if it gets into eyes or other sensitive areas.

When cooking with chillies, removing the seeds and the white pith on the inside of the fruit can reduce the fiery heat. For more intense heat, cook the chillies for longer which will help the oils to develop further.

PROBLEMS WHEN GROWING CHILLIES
Why are the leaves puckered and the buds misshapen?
The most likely reason is aphids which suck the sap from the plants and leave a sticky secretion on which a black sooty mould grows. Aphids will damage the flower buds reducing the amount of fruit that the plant will produce. The problem might also be whitefly which will swarm up into the air if the bush is shaken. Their damage will be obvious from the leaves having a silver-grey look to them. Control both with pyrethrum, Natrasoap or Confidor.

What causes holes or splitting in the fruit?
Although you might not want to bite into a raw chilli, the eggplant caterpillar, potato tuber moth and heliothis don’t seem to mind it and these will be what are causing small holes in the fruit. Once they are inside, it is impossible to do anything but their numbers can be controlled by destroying all affected fruit and vegies in the garden. Products such as Success or dipel will help to control large numbers of caterpillars.

Splitting of the fruit is caused by low temperatures. Apply seaweed extract weekly to build up the cell walls of the plant and consider whether the bushes were planted too late in the season.

What is the brown mark on the side of the fruit?
If the mark has a firm ridge around the outside of the blotch and the rest of the fruit is healthy, the problem will be blossom-end rot. This is a non-infectious disease caused from environmental issues and is most often found on the first lot of fruit. Check the soil pH is not below 6 and correct with lime if necessary, avoid fluctuations in water applications and mulch well. Remove any weeds or other plants that are close by to reduce humidity if at all possible.

Alternatively, if there is a bleached edge to the mark, it is most likely sunburn in which case, try to encourage more leaf cover of the fruit or use Yates Drought Shield to protect the fruit. Weekly applications of seaweed extract will also help.

Why doesn’t my bush produce much fruit?
Over fertilising will cause the bush to produce lots of foliage but not much fruit. Reduce the amount of fertiliser applied or switch to a low-nitrogen fertiliser which is specifically designed for fruiting plants.

Why are the leaves going yellow?
This could be caused by a lack of fertiliser. Apply a liquid fertiliser immediately to provide the plant with a good boost but also side-dress with a controlled release fertiliser which the plant will continue to absorb over a long period of time. If you feel that the plant has been given plenty of fertiliser but the leaves are still yellow, check and then correct the pH of the soil as this will affect the plants ability to absorb the nutrients that you have provided.

If the leaves yellow and then drop off, the cause may be diseases. Bacterial spot is evident from black spots on the leaves and is often prevalent in wet windy weather. Alternatively, it could be powdery mildew which is generally a dry weather problem.

Why has my plant wilted suddenly?
Apart from the most obvious cause which is either too much or too little water, plants may wilt because of root-rot diseases from the soil or from insect damage to the roots such as nematodes. There may also be damage to the base of the stem which has allowed infection to get in. For younger plants, the problem may be cutworm which live in the soil be damage the stems at night. Try Success or drench the soil around the plant with Baythroid.

Once damage is done, it is almost impossible to repair so the best way forward is to plant into a different position ensuring that the soil is well prepared and at the correct pH and that the plant has full sun and a steady supply of water without over-watering. Keep weeds away and mulch well but ensure that it doesn’t touch the stems. Apply seaweed extract regularly to ensure that they are as healthy as possible.

Why is the fruit cracked?
This is caused by the soil drying out between watering or possibly rain in summer causing very rapid growth. Chilli bushes require a steady supply of moisture without being too wet so trickle irrigation used regularly with a decent covering of mulch will prevent the soil from drying out. Applications of seaweed extract will help in extremes of weather.

HOMEMADE CHILLI PESTICIDE
Boil 4 chopped garlic cloves, 4 chopped onions and 6 chopped chillies in two litres of water for 25 minutes. Add two tablespoons of grated natural soap and allow it to dissolve and then cool. Strain the mixture into a jar through an old stocking.

To use, mix one part chilli liquid with two parts water and apply with a spray bottle. Apply every 2 to 3 days or more often where overhead sprinklers are used or when rain has occurred.