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Cultivation basics for Clivia

Clivia are happy in pots or in the garden in a well-lit shaded position. They can tolerate morning sun or filtered light but will burn in full sun. Planting them in a very dark area of the garden may result in a lack of flowering as they need light in order to produce flowers. Often people plant them under a deciduous tree and this is fine provided they do not get too much sun when the tree is bare, or are exposed to frost. Clivia do not handle frost and will end up with damaged leaves or worse.

Planting
They can be planted any time of the year but best to avoid extreme days where frost is expected, storms or very high temperatures. Plants from Clivia Market have been grown in shade houses that are not heated or in outside shaded areas, so there is no need for them to acclimatise. Very young seedlings can be fragile and are best kept in a pot until at least 2 years of age (around 5 leaves). It is recommended that seedlings in particular are staked to help them to establish. A bamboo stake and soft ties are easy to remove in the future when the plant is established. This can be determined by gently rocking the base of the plant. If there is movement, then the plant has not established yet. If the plant feels like it is not moving, then the stake and tie can be removed.

Soil and watering
Clivia need a well-drained medium where the water will drain away from the roots of the plant. Sitting in wet or soggy soil will result in root rot and the plant ‘falling over’. Clivia are better kept on the dry side than too wet. Adding coarse orchid mix to the soil around the plant when planting can help to prevent the plant sitting in wet soil.

Always water the Clivia in when first planted (Seasol is a good tonic for newly planted Clivia). Once established, Clivia in the garden barely need any water. They can survive easily on the natural rain fall. In summer they will benefit from weekly watering if there is insufficient rain. Younger seedlings may require more regular watering than mature plants. If the plants are in an under-cover area, they may need the occasional water over winter and weekly water over summer.

Fertilising
Clivia love being fertilised and will produce darker green leaves and better flowerings when fertilised. It also assists them in fighting off diseases or pests when they are strong and healthy. A slow-release fertiliser is recommended such as Osmocote. The occasional drink from a watering can of a diluted liquid fertiliser, such as Thrive, Charlie Carp etc. also helps. The only fertiliser I would not use on a mature plant is one very high in nitrogen as it will promote leaf growth rather than flowering.

Pests and diseases
The biggest enemy of the Clivia gardener is the mealy bug. They will strike whether the plant is in the garden or a pot. Often the damage is done before they are discovered. These pests are small white bugs with a tail and can be seen on the underside of leaves or in-between leaves along with white cotton-wool looking material. The mealy bugs bite into the leaves and fungus can then get into where the leaves have been bitten. Damage can be extensive if left untreated and possibly result in the plant dying. Mealy bug can be treated with Eco-oil and Eco-neem by diluting to the stated ratio and spraying with small or large spray bottle, depending on the amount of Clivia you have. Always spray under the leaves, between the leaves and around the soil at the base of the plant. You will need to spray again in 2 weeks. A good rule of thumb is to spray plants in warmer months as a preventative measure.
Snails and slugs like to eat leaves and particularly like to eat the flowers. I have not had a problem at my property with snails but have seen slugs occasionally in the shade houses. I have used an old treatment of a plastic container (Chinese take-away) with good size holes drilled into the sides. This is filled with beer and I have had success with slugs drowning in the beer. Obviously this would not work for snails unless the holes were much bigger perhaps.
I also occasionally see ear-wigs between the leaves that bite into the leaves and cause damage. The treatment for mealy bug (Eco-oil, Eco-neem) will take care of the ear-wigs as well.

Rot
Other Clivia problems include crown rot and root rot. Root rot as mentioned earlier, is usually caused by the plant sitting in a soggy medium and not draining well. Symptoms of root rot include yellowing leaves, plant leaning, plant loose in the ground and plant falling over. The treatment is to take the plant out of the ground, remove all soft and rotted material from the roots and base, even if it means there are no roots left. Cover the base and roots with Sulphur Powder or Mancozeb (both available at Bunnings). Do not plant the Clivia back into the same soil. Remove the affected soil as there most likely will be rotted roots and fungal spores in the position where the plant was. If you can, place the plant in a different location or a pot for a while. If you must use the same position, remove affected soil and place some coarse orchid bark in the position to help keep the plant from becoming soggy. The plant will need to be staked until roots establish and kept as dry as possible.
Crown rot is when rot develops on the top of the plant between the leaves. This can be caused by bug damage or water damage from a tree above. All affected leaves need to be removed and all soft and rotted material needs to be cut off the plant. Sulphur Powder or Mancozeb should be applied to the affected area. Mancozeb can be made into a paste with a little bit of water and painted on with a small brush. The plant needs to be kept dry if possible. Depending on how far the rot penetrated the crown of the plant, it is possible that new offsets may develop all around the plant and the mother plant may cease to grow again. This is not the end of the world. One plant may suddenly become six plants. You just have to be patient and realise it may not look as good for a while.

Pot Culture
Clivia are happy in pots and make amazing looking feature plants in huge pots where they can freely offset. The best medium to use is an orchid bark where the water can drain easily out the bottom of the pot. Water when the medium feels dry (stick your finger down into the mix) and make sure you see the water draining out the bottom of the pot.

They are best located on the south side of a house or under a verandah, or even a good shady tree. They can be kept inside a house but need 6 weeks of cold weather in winter in order to flower. Ensure that where they are located, there is good air flow and no direct sunlight.

Flowering
Generally, Clivia will flower around 5 years of age with around 12+ leaves. Miniata flower in Spring (September) but may flower out of season now and again. A flower spike develops down between the leaves around July/August and may become damaged if hit by heavy rains or hail. The flowers will be open for a few weeks and may be pollinated by bees or other insects. If pollinated, berries will form that are green until they are ripe around June/July. When ripe, orange flowers will have red berries, yellow flowers will have yellow berries and peach flowers will have peach berries.

Reasons for plant not flowering:

  • Plant is too young
  • Plant was under stress at the time the flower embryo should form (January- – February)
  • Plant is in a location that is too dark
  • Plant is not healthy (has rot, insect infestation, needs water or fertiliser)
  • Plant produced many flower heads and berries the year before and is recovering
  • Plant did not get cold enough over winter. Clivia need 6 weeks of cold temperatures in order to flower in Spring. Plants kept in pots in the house may not flower if kept warm over winter
  • Sometimes we cannot determine a reason.