Botanical name: Crassula cotyledonis
Synonmys: Crassula dubia, Purgosea cotyledonis
Crassula cotyledonis also called Crassula dubia is a small succulent shrub with broad, paddle-shaped, blue-gray leaves covered in a soft buzz which protects it from intense sunlight.
Crassula dubia leaves are borne opposite on the stem and develop a soft pink tinge along the leaf margin in bright light or under direct sunlight.
The thick ovate leaves are smaller at the base and get larger towards the top of the stem. Avoid handling the leaves excessively as they lose their coating when they come into contact with oil.
Crassula dubia Succulent blooms from late spring to summer with cream to yellow, bell-shaped flowers. The flowers are borne above the foliage on a tall flower-stalk.
Crassula dubia grows to a height of about 8 in. and about 1 ft wide.
Crassula cotyledonis or Purgosea cotyledonis is endemic to South Africa in the arid Namaqualand and Karoo Regions where it grows on hilltops, slopes, very rocky ground and outcrops.
Crassula cotyledonis (Crassula dubia) thrives in bright light with direct sunlight of at least 4-6 hours, average warmth and moderately moist, well-drained soil which is low in organic matter coupled with monthly feeding during the growing season.
Crassula dubia has no need for extra humidity. Repotting is only needed when it becomes pot-bound or when the potting medium is completely broken down. Pruning is necessary to keep the plant neat, to discourage pest and disease infestations and to rejuvenate growth. Keep reading for more on these growing conditions and how to achieve them.
Crassula cotyledonis requires bright light with at least 4-6 hours of morning or afternoon sunlight. Keep it away from hot direct sunshine to prevent scorching of the leaves.
Crassula dubia can be grown outdoors, however, gradually acclimate it and place it in a shaded place first to prevent scorching of the leaves.
Rotate the pot regularly to ensure that the plant receives light on all sides for uniform growth.
If the light is not adequate, the plant will become leggy with elongated stems and undersized leaves.
Crassula cotyledonis can also be grown under a grow light where the natural lighting is not sufficient.
Water Crassula cotyledonis liberally during the growing season and allow the soil to dry out between waterings to avoid rotting.
Reduce watering in the cold season as growth is minimal at this time and the plant does not need a lot of water for growth.
Only water the plant with water that is at room temperature to to prevent plant shock as it can result in brown leaf spots and reduced growth.
Ascertain that the pot has a drainage hole and the soil is fast-draining to prevent the plant from sitting in soggy soil as it can lead to rotting and death of the plant.
Take care not to wet the foliage to avoid fungal diseases or water from the bottom instead and always empty the bottom saucer (plate) once the plant has absorbed enough water.
Crassula cotyledonis requires an average warmth between 15-240C during the growing season and a minimum of 100C in the cold season.
Keep Crassula dubia away from frost and cold drafts like windy doors and windows, air conditioning units among others as they can cause the death of the plant.
Crassula cotyledonis has no need for extra humidity. Average room humidity is adequate for this plant.
Make sure that there is good air circulation for the Crassula dubia to prevent fungal disease infestations which are prevalent in overwet, poorly aerated conditions.
Crassula cotyledonis is a slow grower, therefore, feed it monthly during the growing season with a Cactus and Succulents Fertilizer to promote growth.
Withhold feeding for Crassula dubia in the cold season as growth is reduced and feeding at this time can cause fertilizer burn and eventual death of the plant.
Repot Crassula cotyledonis at the beginning of the growing season only when it has become pot-bound or when the potting medium has completely broken down. Use a pot that is 1 size larger than the current one to avoid overpotting and retention of excess moisture.
Confirm that the pot has a drainage hole and that the soil is free-draining to prevent it from getting soggy to avoid root-rot and eventual loss of the plant.
Use a clay pot instead of a plastic or ceramic pot as a clay pot is porous and allows the soil to dry out faster to keep it from staying wet for too long.
Before repotting, make sure that the soil is dry. Take the Crassula cotyledonis out of its pot and brush off soil from the roots. Snip off any dead or dry roots and treat the wounds with a fungicidal solution.
Position the plant in the center of its new pot and back fill with fresh, loose, fast-draining soil while spreading the roots as you fill the pot.
Do not fill the pot completely but leave about 1 in. unfilled to allow for watering space.
Replace the plant to its display position and keep it dry for about 5-7 days to reduce the risk of rot-root disease.
The best soil for Crassula cotyledonis should be coarse, low in organic matter and one that drains fast to prevent it from getting soggy. The soil should be loose enough to allow water to drain out quickly.
Cactus and Succulents soils like these Cactus and Succulents Mixes available online at Etsy are ideal for the Crassula dubia.
Pruning Crassula cotyledonis involves removal of any dead or diseased leaves to keep it neat and reduce pest and disease infestations.
Snip the leaves at the base with a sterilized knife or pair of scissors to prevent diseases transmission.
Cut back the plant at the beginning of the growing season if it is has become too large and unruly to encourage a compact growth.
Minimize the number of cuts as much as possible to avoid unnecessary injuries to reduce fungal disease infestations.
Crassula cotyledonis (Crassula dubia) can be propagated at the beginning of the growing season from offsets, leaf cuttings or stem cuttings.
Take 2-3 in. stem cuttings from a healthy Crassula cotyledonis and allow the cutting to dry out (callus) for a few days.
Once callused, insert the lower cut end of the stem cuttings in moist, loose, fast-draining, rooting soil.
Position the set up in a well-lit, warm place away from direct sunlight to avoid cooking the cuttings.
Maintain the soil slightly moist until the stem cuttings are rooted. Rooting may take about 2-3 weeks.
Make sure that there is good air circulation to minimize the risk of fungal diseases infestations.
Allow enough time for substancial growth before transplanting the new Crassula dubia after which you can begin routine care.
Carefully seperate the offset from the mother Crassula cotyledonis by cutting with a clean, sharp knife while ensuring that the offset has adequate roots.
Pot the offset in its individual pot in moist, loose, fast-draining soil and place in a warm, well-lit place away from direct sunlight.
Ascertain that there is good air circulation to prevent fungal diseases infestation.
Keep the soil slightly moist through out until the new Crassula dubia is well established after which you can begin routine care.
Take leaf cuttings complete with the petiole from a healthy Crassula cotyledonis. Allow the leaf cutting to dry out (callus) for a few days to prevent rotting.
Once calloussed, lay the leaf cutting on moist, fast-draining, rooting mix while ensuring that the cut end does not come into contact with the soil to prevent rotting.
Place the set up in a warm, well-lit place away from direct sunlight to prevent scorching of the leaf cuttings.
Maintain the soil slight moist through out. Ensure that there is good air circulation to prevent fungal diseases.
With time, the leaf cutting will form roots and eventually a small rosette will form at the base of the leaf cutting. This may take from 4-6 weeks.
Allow substancial growth of the rosette before transplanting the new Crassula dubia into individual pot after which routine care can begin.
Crassula cotyledonis (Crassula dubia) problems indoors include wilting leaves, leggy growth, leaf spots, pests and diseases among others. Keep reading for more on these problems and how to fix them.
Leggy growth and undersized leaves in Crassula cotyledonis is due to two possible reasons. One possible reason is overwatering or soggy soil in the cold season.
Significantly, cut down on watering in the cold season as growth is reduced at this time, therefore, the plant does not need a much water.
In addition, make sure that the pot has a drainage hole and that the soil drains easily to prevent it from getting soggy.
The second possible reason for leggy growth and undersized leaves in Crassula dubia is too little light during the growing season.
Place the plant in bright light with at least 4-6 hours of direct sunlight during the growing season or instal a grow light if the natural lighting is not sufficient.
Wilted and drooping Leaves in Crassula cotyledonis are caused by underwatering which results in too little moisture in the soil. Therefore, the plant cannot get enough water to take up to the leaves which loss their turgidity and begin to wilt and droop.
To prevent wilting and droopy leaves, water the plant deeply during the growing season and allow the soil to dry out between waterings.
Decrease watering in the cold season but do not allow the soil to dry out completely for a prolonged period of time.
Brown soft leaf spots in Crassula cotyledonis are caused by leaf spot disease which is prevalent in poorly aerated, overwet conditions.
Better the ventilation and make sure that there is good air circulation at all times. Also, water the Crassula dubia from the bottom to avoid wetting the leaves.
Crassula cotyledonis is also prone to powdery mildew which is enhanced by overwet conditions coupled with poor air circulation.
Isolate the affected plant to reduce spread to other houseplants and treat it with Neem oil. Improve ventilation and make sure that there is good air circulation for the plant.
Water the Crassula dubia from the bottom to avoid wetting the rosette of leaves and always allow the soil to dry out between waterings.
Do not allow the plant to sit in soggy soil; always empty the bottom saucer (plate) once the plant has absorbed enough water.
Make sure that the pot has a drainage hole and that the soil drains out easily to prevent it from getting soggy.
Common pests in Crassula cotyledonis are scale insects, mealy bugs and spider mites. Isolate the affected plant to prevent spread to the rest of houseplants.
Spray the plant with an Insecticidal soap to get rid of the pests. Make sure to cover the entire plant.
Crassula cotyledonis (Crassula dubia) like its cousin, Jade Plant, is considered to be toxic to both humans and pets as outlined by ASPCA.If ingested it can cause nausea, vomiting and diarrhea. Keep the plant away from the reach of children and pets.