I just killed my favorite Haworthia.

It was a beautiful rock hard reptilian looking specimen I'd had for years in a lovely handmade pot. I failed to follow my own advice to back off prior to coming humidity because I wasn't paying attention. But of course it was so hot and they started to shrink so they must need water, right? Wrong.

Haworthias are common green succulents that are usually hard to the touch. They are among the few groups that stand up to our heat, living long and growing quite large after just a year or two. But this is a drought lover, naturally, not a coastal succulent, so it's not as geared for heat and humidity and watering all in the same week or two. After the recent summer storms it died from rapid rot inside the rosette.

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This was about evaporation rates which are key to growing here in the desert. Before humidity arrived we were routinely way below 10%. At that low level everything evaporates instantly. A small potted plant will be totally dry a day or two after watering. Under such conditions it's hard to overwater cactus and succulents in properly draining soil. Plants are adapted to survive these dry periods during the heat of summer by slowing their metabolism to become semi-dormant until conditions return for growth. Therefore despite extreme heat, water demands are minimal.

The humidity rates suddenly went up to an extended 70-80% with the latest tropical storms. Moisture existing in a potted plant root zone will remain there unchanged for weeks under this situation. No evaporation or only slight. These plants are not accustomed to lingering moisture in the root zone during the hot season. This scenario may have taken more than just my prize haworthia. Everyone gets meltdown and most of the time they don't know why.

You visit my garden or Moorten Botanical Garden in late summer, things may appear dry and even drier in the Cactarium where evaporation rates are limited. We have learned through many painful losses of specimen plants that it is far better to err on the side of too little water as it won't kill succulents this time of year. Sure they might look a little rough but don't worry, it's normal. One ill-timed watering lets the rot process begin as the root crown is steamed like broccoli to a soft, mushy mess.

You're facing meltdowns, know that some plants can be saved while for others it is almost certainly fatal. Bigger plants with extensive stems, trunks and caudexes are expensive and worth trying to save as they can be a decade old and costly to replace. The moment you discover the problem take the plant out of the pot and remove all soil from the roots. Total exposure is essential to ascertaining the extent of the rot.

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Surgically cut out all brown rot and damage with a sharp, sterile knife. Take a good margin leaving only undamaged tissue. Place the naked plant in the shade outdoors for a week of dry weather to allow the exposed flesh to callus off and heal properly. Once it's stabilized you can repot again with new cactus potting soil for recovery during the cool fall months. Sure it will not be as beautiful as before, but it will survive and regrow again.

Under such conditions during this transitional monsoon season, dry plants can be helped through without water by using shade cloth. A small drape helps keep the plant cooler so it weathers dry heat more easily with some temporary shade. When humidity arrives and UV declines, open it up again so the moist air can be taken in via tiny pores called stomates.

A collection of prized cactus and succulents is tricky to manage this time of year. You can't just water them all equally. Care must be taken to consider pot size, soil type, plant species, its origins, and true moisture demands. Late summer meltdown strikes us all, but at least I get to shop for a replacement when the winter resort Season gears up again next month.