Spiky Silhouettes: Growing Healthy Cacti & Succulents
Optimal growing conditions & environment = Healthy cacti & succulents.
· - Ensure proper and adequate lighting. Not too much but not too little.
· - Avoid overwatering, underwatering and inconsistent watering.
· - Provide cacti and succulents with well-draining, coarse organic potting mix.
· - When necessary, always use clean and sterilized pruners or cutting tools.
· - Use minimal fertilizer applications with low nitrogen content.
· - Ensure plants have proper ventilation and good air circulation.
Common Issues & Symptoms
Brown scaring or callusing – Typically caused by sun burning or sun scald. It can sometimes be due to spider mite damage.
Solution: Avoid placing susceptible plants in direct, intense sun exposures. Young plants or plants with fresh new growth are more susceptible to sun burning. Protect plants with burlap sheets or shade cloth or similar while they are transitioning to full sun locations. Spider mite infestations can cause brown scale or surface tissue scarring. Although this type of damage is permanent, depending on the variety of cacti, new cuts may be taken from unaffected parts and re-rooted to start new, healthy plants. For Agaves and other types of succulents will need to grow out of such damage by forming new leaves.
Growth Deformities – Can be caused by several different abiotic conditions or viral infections.
Etiolation - is the common term for stretched weak, pale or constricted growth. This is a condition caused by a lack of adequate light. The plant’s cells elongate to allow the plant to reach for more light which causes weak tissue growth. These changes cannot be reversed once they occur. With some cacti this can be corrected by removing some plant parts or making cuttings from healthy tissue, etc. But if the mother plant is deformed it will never be 100% healthy again.
Solution: Provide the correct level of light for the cacti or succulent you have. If natural light is not adequate utilize the proper LED growth lights while plants are indoors.
Growth Rings – These typically occur due to inconsistent watering patterns. Often seen on columnar or cereus type cacti or sometimes on globose varieties. Symptoms appear as a thick section followed by a constriction then another thick section. As expected, the thicker section is due to an increase in water absorption.
Solution: Maintain consistent watering, especially during periods of growth in spring and summer. Cacti and succulents’ roots are opportunistic and efficient. When given more water to drink, they usually will and store it for later, but when roots are too wet, rot can occur. Avoid unnecessary fertilization.
Stunted growth or Twisted stems – Can be caused by insect feeding, mechanical damage or viral infections. Common insects that feed on cacti and succulents have piercing/sucking mouth parts which can lead to physical deformities or stunted growth. Twisted stems can occur after insect infestations or feedings. They can also occur due to viral infections that were vectored to the plant by these types of insects. Stunted growth can also be due to freeze or mechanical damage.
Solution: Prevent insect feeding at all cost. Mealy bugs, spider mites, aphids, scale and sometimes whitefly can all be problematic on cacti and succulents. Organic insecticidal soaps, or horticultural oil products are good options to help control these pests. Often, washing plants off with a blast of water from the hose, or physically picking off or wiping are also excellent options. Obviously, plants with spines present a prickly problem, so spraying may be your only option. Also, protect plants from frosts or mechanical damage from things like hail or rodent chewing.
Rot or Tissue Collapse – are almost always associated with soils that stay too wet for too long while cacti or succulents are not actively growing. It is important to understand that rots are not necessarily caused by watering too much. It could be, but most commonly it is due to soils that stay too wet while the plant roots are not using that moisture. Roots that are in contact with moist soil can become waterlogged and then tissues rot. Root rotting pathogens travel up into the body of the plant through its vascular system and often cause pockets of water-soaked, collapsed tissue. Likewise, surface moisture contacting tissue walls, scars or damage can lead to secondary fungal infections which can cause plants to rot. Often, by the time rot is discovered, it has caused catastrophic damage. Occasionally, rot damaged areas or lesions can be cut out, or rather healthy parts of the cacti can be carefully & cleanly removed, to then be re-rooted to regenerate the plant.
Solution: Always, use proper, well-drained soils, avoid over-watering, especially during no growth periods, allow soils to dry thoroughly between waterings, and avoid splashing plants with water during summer. At planting time, it can be advantageous to provide a layer of non-organic, water-wicking material between the soil and the base of the plant, especially for immature or young plants. When planting in pots, choose a size that is 1-2in. larger than the pot the plant came out of; in other words, avoid containers that are too large. Larger soil volumes hold too much moisture. Last but not least, avoid exposing non-hardy cacti or succulents to cold or freezing temperatures.
Questions...? Email us directly: happyvalleyplants@gmail.com
