During the summer heat damage can affect your orchids. If your plant is showing the common signs of heat damage, you need to assess the damage and take steps to salvage your orchid.
Signs of Heat Stress and Damage
One of the best advantages of having orchids is that they let you know immediately if there is a problem. If you have accidentally left your orchid outside, in the car, or under an artificial light for too long, then immediately check for these signs of heat stress and subsequent damage.
- Red or purple tint
- Withering of leaves or flowers.
Much like humans, an orchid can burn, and it will show immediate signs of it. If you see any red or purple on the leaves, then your orchid was likely burned. However, even if you don’t notice any immediate symptoms that does not mean that your orchid was not damaged.
Other symptoms of a heat stressed or damaged orchid that may show up within 24-48 hours after exposure are:
- Yellowing leaves and/or stems
- Withering leaves
- Brown leaf tips and roots
- Bud blasting (loss of buds)
- Flowers dropping prematurely
- Withered pseudobulbs
Browned and burned roots in combination with the dried up pseudobulbs means that your poor orchid has little to no chance of recovery because the pseudobulbs are the moisture reserves. Under these conditions, pseudobulbs will only drain in cases of extreme heat exposure.
What To Do for a Heat Damaged Orchid
Most people have an immediate response to over water anything that is dehydrated. Unfortunately, like most things, orchids can only absorb so much water at one time. This means that if you were to pour in copious amounts of water to “help” the heat damaged plant, then you can cause even more problems associated with overwatering – mainly root rot.
Follow these steps to help begin the recovery process for your plant:
- Immediately remove the orchid from the sun/heat and place it in a cool area with plenty of ventilation.
- Assess the damage to the plant and look for leaves and blooms that are heavily affected. If there are areas that are completely damaged, remove them and the blooms to prevent the orchid from spending unnecessary resources on them and focusing more on the rest of the plant.
- If there are exposed roots that are severely damaged and burned from the sun, cut them as well. Your orchid will likely go into shock from the dehydration alone as well as the trimming of roots, but preventing root rot is essential.
- Avoid fertilizers for a few months. If your orchid has been burned, putting chemicals and fertilizers on it may only increase the damage. This is a common mistake and should be avoided on burned or sun damaged orchids.
- Water the orchid normal amounts, but slightly more frequently. Check the moisture levels in your moss to ensure that it is being properly soaked up and no rot is setting in.
Sometimes it may be necessary to cut back the orchid completely and leave just the stem and roots. This should only be done in the event of severe sun damage and dehydration. Once you have determined that all significant damage has been removed from the plant, you should look for a snug clay pot for your orchid to replant it. Use plenty of long strand sphagnum moss that has been soaked the previous night and make sure that it is kept in a well-ventilated area to prevent water retention and further damage.
With luck, your orchid should grow back. Avoid fertilizers for a few weeks until you see regrowth. Once you have determined that your repotting is successful and that the orchid is growing, you can use diluted fertilizers to aid it until it has made a full recovery. Also keep an eye open for pests or viruses because they are more susceptible after a trauma like heat exposure.
Orchid Types and Heat Damage
Some varieties of orchids react more strongly to heat than others, like mounted orchids. These orchids are highly sensitive to heat because they lack the protective pot and extensive moss that helps keep the roots safe in potted variants.
Expect more frequent watering for mounted orchids and expect more root damage in the event of these orchids being left in the sun for too long. Since the roots are completely exposed, a mounted orchid can have its entire root system irreparably destroyed by the sun thanks to the lack of protection.
Mary Ann Berdak is the publisher of OrchidCareZone.com an online destination for orchid growing tips and advice. For more information on orchid care download her free report, “The 5 Biggest Orchid Mistakes (and How to Avoid Them!), at OrchidSecretsRevealed.com.