Gardening: Growing succulents in Whanganui

San Pedro cactus produces sweetly scented, large and exotic creamy white flowers.

Gareth Carter is the general manager of Springvale Garden Centre in Whanganui.

OPINION

The recent weeks of warm summer temperatures are excellent for seeing growth of drought-hardy plants such as succulents and cacti.

These structural plants provide an architectural form that thrive in the heat.

Succulents and cacti offer a stylish solution for dry parts of the garden, pots and hanging baskets where watering is not easy or is often forgotten.

The distinguishing feature of succulents is their ability to withstand long periods of drought.

This is due to the presence of water storing fleshy tissue in the stems, leaves or roots.

Cacti have structures called areoles – cushion like growths on their stems from which the spines, hairs, flowers and shoots develop.

Succulents and cacti display a unique variety of size, shape, colour and texture.

Many flower only for short periods and produce large brightly coloured flowers, while others flower for longer periods, producing an abundance of exquisite flowers.

They fulfil the need for tidy and colourful plants in various areas around the home for many years with little maintenance compared with other plants.

Many succulents and cacti can be grown as indoor or outdoor plants.

The hardier species can make a beautiful garden display and in hot dry spots there is an opportunity to create an outdoor desert garden.

Whether you grow them as single specimens or as a diverse group, their tolerance of dry conditions make them also ideal for containers both indoors and out.

They often make ideal pot plants for a sunny windowsill, balcony, deck or patio.

When growing in pots, use a specialist potting mix such as Yates Thrive Succulent & Cacti Mix, designed to be well drained and with the right nutrients, this will give great results.

An addition of a slow release fertiliser such as Ican Slow Food each year will ensure continued health and growth of these plants.

Growing indoors

Many succulents and cacti will thrive in containers and indoors if provided with warm temperatures and bright light.

Use small pots for individual plants or large bowls for planting a selection of compatible species together.

Gloves should be worn when handling prickly or spiny plants such as agave, aloe and opuntia because their sharp spines can easily become embedded in your fingers if you brush against them and be quite painful.

The use of kitchen tongs is also quite useful when handling them.

Bowls can be very effective for growing succulent and cacti plants indoors.

One or two plants with a columnar habit can provide the focal point of the bowl or a leafy succulent such as the Jade Plant (Crassula ovata) as the main plant.

The rest of the bowl can be filled with small plants such as echeveria and lithops succulents are really fun to grow in containers because they don’t complain or suffer when neglected like most other pot plants do.

Many can be grown for longer before they need repotting.

San Pedro cactus

Also known as Trichocereus Pachanoi, the San Pedro cactus is a popular cacti for growing both outdoors or indoors as a house plant.

San Pedro produces sweetly scented, large and exotic creamy white flowers. Each bloom lasts a couple of days, after which it shrivels up and falls to the ground.

Thriving on neglect, this plant can make an ideal gift for the gardener or non-gardener.

Originating from the Ande mountains at 2000-3000m altitude, it is also found in Peru, Argentina, Bolivia, Chile and Ecuador.

It will tolerate down to -9C but grows faster in warmer temperatures.

It is relatively fast-growing and forms an attractive column. As it grows larger multiple stems are formed.

Most cacti are slow growers of approximately 2cm a year. San Pedro cacti can average up to 30cm annually in a warm well lit growing position.

Eventually if grown to full size the San Pedro can reach 6m tall.

Lithops

This unique succulent is commonly known as flowering stones or living stones.

This is because their shape, size and colour looks like that of small pebbles or stones.

They occur naturally in large areas of West Africa where little rain falls.

The body of the plant is made up of two fleshy leaves that are fused together.

These store water which enables them to live in areas of extreme drought and go for a number of months without water.

In cultivation they can be grown indoors or out. They make an ideal easy-care houseplant as long as they receive 4-5 hours of direct sunlight each day.

A north or west-facing windowsill is ideal.

Outdoors they need a free draining spot to cope with the higher rainfall we have here than in their naturally occurring environment.

They will cope with this fine as long as the drainage is good.

If you are concerned then the raising of an area with sand, gravel or cacti and succulent mix will facilitate good drainage.

Lithops have a seasonal growth habit and will produce a new set of leaves each autumn.

In the natural habitat, a period of autumn rain will instigate both growth and flowering too.

Spicy sweetly scented yellow or white flowers are generally produced each autumn from when the plant is 3-5 years old.

Outdoor planting

Attractive collections of succulents and cacti grow successfully outdoors.

Remember however that few succulents tolerate excess moisture and virtually all require good drainage.

They grow well in raised beds where water drains away freely and easily.

Succulents are great on the sand country which we have much of around Whanganui.

Opuntia, sedum and sempervivum are among the hardiest.

With sharp drainage and good hot sun in summer a number of desert species of succulents and cacti will withstand cold winter temperatures.

Heavy frost is generally the biggest enemy of succulents.

A heavy frost can burst the cells in the fleshy leaves of succulents which can turn the plant into a brown unattractive mush.

Most of Whanganui has a temperate climate which means this is not an issue.

When growing non–succulent and succulent plants together remember to choose plants that have similar needs for light, soil type and watering.

Annuals such as Portulaca and Livingstone Daisies are suitable for planting outdoors among succulents and cacti.