Even Drought Tolerant Plants Can Sunburn  

Agaves, cacti, and succulents are generally heat & drought tolerant, however, new and immature plants can still develop stress symptoms such as sunburn, sunscald or discolorations. This happens when plants are not properly transitioned to their new location. When moving plants around our nursery, from one spot to another, we often provide additional, temporary shade or protection to ensure plants do not get accidentally damaged this way. In this blog we offer you some valuable tips and techniques we’ve learned ourselves by trial and error.

To avoid heat stress, shock and sunburning following these simple steps

  1. Do your research and choose the proper type plant and species for the planting site and exposure you have.
  2. Harden off new plants in a semi-shaded spot for 7-10 days prior to planting out. Do this whether they are bare root or arrive potted.
    • Do not take them out of the box and plant them in full, hot direct sunlight right away. Give them adequate time for transition.
    • Acclimation to their new environment and garden location is vital for their long-term success. After hardening off but prior to planting, place your new plant in the spot where you intend to plant it for a few more days where you can observe it and ensure a good acclimation transition.

NOTE: For bare root plants, heal the roots into loose peat or 50/50 perlite/potting soil in a pot for their hardening off period. Healing them in helps prevent roots from drying out or becoming too emaciated.  

  1. Once planted, pay close attention to newly planted plants.
    • Yellowing, white to tan colored blotches on leaves or plant flesh are typical signs of sun damage. While this type of damage can cosmetically harm a plant it is not fatal as long as you make proper adjustments. Covering the plant with 50% shade cloth or a piece of burlap is an easy solution to help protect it while it is becoming established. Generally, gardeners in high elevations, low or inland deserts need to be most wary. Once plants become rooted, and more mature, the more acclimated they become.
  2. Make sure soil drainage is optimal, and that you are providing the new plant with appropriate water.
    • Most Agaves, cacti, succulents and yuccas perform best in loose, well-drained soil.
    • Water new plants thoroughly after planting, then apply adequate water according to the plant’s needs, soil composition, drainage, temperatures, humidity, sunlight, etc. Water the soil at the base of the plant, avoid wetting the foliage or flesh. Water sitting on leaves, at the base of the leaves or on the crown can be problematic initially.
    • When potting plants, use a fresh, sterile well-draining cactus mix or a premium potting mix. Pre-moisten it, since loose soil mixes tend to resist hydration. It should be moist enough to become sticky, but not saturated. If you squeeze a handful of moistened soil water should not drip out, but it should stick together.

NOTE: Newly planted bare root plants will not use as much water as potted plants or established plants. The roots they arrive with have little to no water absorption capability. These roots mostly provide anchorage and that’s it. Bare root plants must grow all new roots to start absorbing water from the soil. Therefore, be judicious when watering new cacti & succulents. Too much water can lead to root rot issues, but hot, dry soil or hot hose water can damage new plants as well.

Questions or Troubleshooting?

Questions or want more advice? Email us: happyvalleyplants@gmail.com

For troubleshooting issues, problems or plant behaviors you do not understand, email us a couple of photos of the symptoms. Pictures can help us to help you identify what the problem is and what you can do to fix it.


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