A Primer for Treating Cold Damaged Palm

[Tala]

We need to exhibit some patience right now. There are no guarantees based on appearances. Some palms will recover, some will not. But there are a few rules that have served me (and plenty of others) well over the yrs.

For heavily damaged (defoliated palms):

if it is a crownshaft species (Adonidia, Wodyetia, Archontophoenix, etc.) I go right to the copper treatment, don't wait but a few days. These palms are notorious for harboring bacteria in their buds which often results in the collapsing of the meristem as the weather warms up. Sometimes these palms will suffer little to no foliage damage yet the bud will rot anyway. Always follow the label but generally speaking you can mix 1 to 2 teaspoons per gallon of water. Pour it directly into the bud until begins to back out (it won't take much for small palms). You can wait a bit, see if it drains and pour alittle more in. You don't want it spilling out all over the roots, especially for potted palms. In ground palms its not such a big issue. You can reapply in about 2- 3wks. I never use it more than twice, copper can be toxic to some plants. Some like to use H2O2 for this but there are no proven studies it works. Palms have recovered after it's use but who's to say they wouldn't have recovered regardless? Copper products are the only known cure for bacterial issues in the growing points of palms. Other fungicide products do not work on bacteria. Some are systemic and its never a good idea to apply copper with a systemic; it often has a synergistic quality. So its best to use the copper alone.

If its badly damaged but not a crownshaft palm you need to think about the species - is it an ultra tropical palm (Mauritia, Latania, Cocos) or something a bit tougher. The more tropical it is chances are the more sensitive it is to cold. So you may want to go right to the copper treatment or ... wait until the spear pulls (if it even does). If you suspect cold damage to the bud often this will have a foul odor at the growing point. Gently tug on the unopened spear leaf, pulling it up towards you. If it doesn't pull loose I will wait and check it again a wk later. If it does pull loose you know the palm has suffered some cryptic cold damage. Go ahead and apply the copper.

Often palms will recover on their own even if the spear pulls loose. Now if more than one spear pulls that would be a sign to do something immediately. If just the one pulls you may want to wait and see if the other spears begin to emerge on their own. As we move back into growing weather palms will begin to push the spear up. You can track this progress by marking the spear where it emerges. I use tape or a "permanent" marker for this. If you don't see the spear moving during warm weather that can indicate cold damage. Often the first 2 or 3 new leaves will be a bit smaller than normal, or distorted, scorched looking. If you see this take it as a good sign - your palm has resumed growing on it's own and should recover without any additional measures.

Sometimes you can cut into the meristem of damaged palms to expedite recovery. I normally try to avoid this, especially on palms that have already formed wood (it can cause severe trunk constrictions). Often it rains just before a freeze, and you don't want a lot of cold water just sitting in the bud of an already damaged palm. For crownshaft palms I usually cut in a slant from the middle of the crownshaft to the bottom. This allows any held water to drain. Also I have poked holes w/ a sterilized knife blade or hand pruner into the bottom of the crownshaft. This serves the same purpose. For palms without crownshafts my rule of thumb is measure the size of latest leaf, and and use that measurement to mark my cut. You can even remove a leaf and hold it next to the palm's meristem. I will try to fold the leaf up, like it was before it emerged. This gives a guideline as how far down I can go to cut. You can shorten it up a bit to be safe; after all if you cut out the entire heart the palm will not make any more leaves and is essentially dead. Again this is something I do as a last drastic measure but I have been able to save Bottle palms, Latanias, this way. If its a small palm and you don't want to cut it open you can often remove excess water, rotted tissue with a turkey baster. Its kind of disgusting but it does work. Maybe a shop vac for you more enterprising surgeons.

Lastly its important to resume irrigating and feeding your damaged palms. A healthy palm always recovers much quicker than a nutrient deficient palm. Here palms heavily fertilized before winter usually perform better during cold but thats a different idea for a different thread. Hope this helps.

[Paul The Palm Doctor!]

Super post-freeze advice, Dave, but people have to utilize copper fungicides carefully. It gets toxic at relatively moderate concentrations. I killed two coconut palms in the 1982-83 freeze with copper that I now know I used too "generously."

Palm lovers also need to remember that not all their species will recover. Sometimes the threshold of excess/lethal cold will be breached. This freeze had elements that made it unique and especially damaging, i.e. overall length in days, durations of temperatures below 28 F., and days where high temperatures stayed below 50 F.

Time really is an indicator for life after freezes; this particular event will play out till nid summer, I'd imagine.

Dr. Paul

[gsn]

I have a question Dave..

Do you know of a way to apply the copper if the crown is to high/tall to reach, to pour it in??

I know this sounds like a dumb question ,but thought you might know a secret??

Also are you just recommending putting the copper only in the crown shaft /bud area, and not the entire palm :ie the fronds, lower crown shaft and trunk?

thanks in advance

[Tala]

Paul,

yes too much copper is toxic; hopefully I weas clear enough in the above instructions. Its why I use it only twice at most per damaged palm.

Scott - I have a power spray rig so thats make it easy for me to treat taller palms. What I did was make my own extension out of pvc pipe. I take however many (usually 6 to 8 ft) sections I need and link them each via quick-connect or male/female plastic ends. At the very top I put an elbow piece on there, then quick connect a lightweight aluminum nozzle to it. Then I stand on a ladder if need be, turn on the rig and pump the mix up into the bud, waiting for it to pour back out. Large palms like Sabal, Bismarckia, Washingtonia, Roystonea, etc. can hold alot of water; sometimes thats good sometimes its not. Copper can work on foliar issues but its not something I would recommend to treat cold damage. Nothing helps cold damaged leaves/stems but time (and a pruning tool). What we're interested in is preventing/reducing bacterial bud rot so only apply copper to the bud.

If you can't reach the bud I'm not sure what to advise you; some systemic fungicides can be applied to the rootzone and watered in but again these do absolutely nothing for bacteria bud rot. If you're in metro Orlando I'm available for hire ...

[Tim Wade]

Thanks for the primer, but any specific advice for a 6-year old Ravenala madagascariensis? I am in zone 10 with 15' fronds that have green showing (stems) up to about 8-10' and many smaller leaves near the ground are undamaged. Only the top seems to have taken the brunt of the freeze. Do I have to look at those giant dead fronds all winter? The bougainvillea and ferns also go whacked but will come back sooner, obviously. Thanks again!

[Tala]

Thanks for the primer, but any specific advice for a 6-year old Ravenala madagascariensis? I am in zone 10 with 15' fronds that have green showing (stems) up to about 8-10' and many smaller leaves near the ground are undamaged. Only the top seems to have taken the brunt of the freeze. Do I have to look at those giant dead fronds all winter? The bougainvillea and ferns also go whacked but will come back sooner, obviously. Thanks again!

Hey Tim,

your plant is not actually a palm at all, but closely allied with other Bird of Paradise plants, Strelitzia I think it is. But we do grow these here, they are easily damaged by temps below freezing. What we do is treat them like bananas (another close rel.) - just cut off the brown leaves, as the weather warms up they are replaced. As you prob. know new leaves emerge from the center, as long as you see this happening your plant will recover just fine. If it has some green left I doubt if it will die. Don't let the soil dry out, keep moist but not water-logged. You can lightly fertilize now but I usually wait until March.

Bougainvillea we cut to the ground here after cold damage, they grow back so fast by the middle of Spring you'd never know anything happened to them. This also the one time its good to give them fertilizer. The rest of the yr don't feed, you get more brachts/flowers.

[newtothis]

can we open discussion here on CIDP or should I start a new thread? My 2 largest planted CIDP spears did not pull, but they are brown on the tops of leaves/still green underneath and on base. I think these will be OK.

About half of my 2 year old seedlings however lost 1 or 2 spears pulled leaving a hole in the middle. I poured hydrogen peroxide today down those but I'd like to hear if others experienced that after this months freeze and what they are doing?

[Tim Wade]

Thanks for the primer, but any specific advice for a 6-year old Ravenala madagascariensis? I am in zone 10 with 15' fronds that have green showing (stems) up to about 8-10' and many smaller leaves near the ground are undamaged. Only the top seems to have taken the brunt of the freeze. Do I have to look at those giant dead fronds all winter? The bougainvillea and ferns also go whacked but will come back sooner, obviously. Thanks again!

Hey Tim,

your plant is not actually a palm at all, but closely allied with other Bird of Paradise plants, Strelitzia I think it is. But we do grow these here, they are easily damaged by temps below freezing. What we do is treat them like bananas (another close rel.) - just cut off the brown leaves, as the weather warms up they are replaced. As you prob. know new leaves emerge from the center, as long as you see this happening your plant will recover just fine. If it has some green left I doubt if it will die. Don't let the soil dry out, keep moist but not water-logged. You can lightly fertilize now but I usually wait until March.

Bougainvillea we cut to the ground here after cold damage, they grow back so fast by the middle of Spring you'd never know anything happened to them. This also the one time its good to give them fertilizer. The rest of the yr don't feed, you get more brachts/flowers.

thanks, Dave. I kind of figured the ravenala would be less sensitive. I can see there is new growth already. The bougainvillea I had just cut back from completely overgrown (we were away in So. America for a few years) before the freeze came along, so there isn't much to cut back now other than the few green (now brown) shoots I left to help train it on the fence top. I will go ahead an fertilize pretty soon as I think the warmer weather is pretty consistent now in Tampa. I think I will wait to cut the dead fronds off the ravenala for a bit just in case we get another cold snap. By early Feb, we should be in the clear. Many thanks again, Tim.

[Tala]

can we open discussion here on CIDP or should I start a new thread? My 2 largest planted CIDP spears did not pull, but they are brown on the tops of leaves/still green underneath and on base. I think these will be OK.

About half of my 2 year old seedlings however lost 1 or 2 spears pulled leaving a hole in the middle. I poured hydrogen peroxide today down those but I'd like to hear if others experienced that after this months freeze and what they are doing?

You must in a very cold place for CI dates to be damaged, altho' its not that unusual for very young palms to lose a spear during prolonged cold. As mentioned above the peroxide is not necessarily a cure, some swear by it but copper is the only documented treatment for bacterial bud rot. What did your palms do after being treated w/ H2O2? Since the spears to your palms still have some green left I doubt they will perish, leftover green is always a good sign. You may want to apply copper just the one time as a safeguard. Keep the palms in a warm sunny spot, and with reg. watering in a fast draining mix they should grow out fine.