Misting over winter

Right then, we've been talking around this subject for a while, and Betty said that she had sat in on a lecture recently, so I'm hoping to hear from her as well.

Seedlings: CAN'T dry out over winter, they need water, but they can get waterlogged and die from too much water.

Cacti Plants: SOME plants like to stay completely dry over winter.

I've noticed some of my button types are starting to shrivel, so obviously they need water, or do they? Do I let them all deflate and go flat? Maybe a light misting is the order of the day, like Lithops a general misting in the morning and as long as they dry by the end of the days is good?

What are peoples views on winter watering, or it is actually still autum (but cold) here, so they need the odd water and they won't shrivel when they are truely dormant?

Another question: How do I know when they ARE dormant?

Food for thought, or discussion?

calycium wrote:

I've noticed some of my button types are starting to shrivel, so obviously they need water, or do they?

NO!! your plants are going dormant, its perfectly normal. a good thing.That, or you haven't watered in a long time and they have no choice but to go spongy. As a very general rule, Mexican cacti do like to be kept completely dry over winter, whilst some South Americans like to be mist sprayed/very lightly watered occasionally over the winter period.

As for deciding whether a plant is going dormant or not, it can be surprisingly difficult. some plants (like one of my crazy Astrophytum myriostigma nudums) are still growing and flowering now with rainy overcaste days, 6C morning starts and a top temperature of 13C!, whilst all the other members of the same genus growing under identical conditions have been dormant for a few weeks. General things to look for include no signs of new growth and sometimes the plant body becoming soft.

Another point i'd like to make regarding this issue is that Melocactus (and also/perhaps Uebelmannias) should not be allowed to dry out completely at any time. even in winter. the biggest killer of Melos is underwatering. mist spray/water lightly these plants when dormant on a regular basis, depending on your climate. yes, i do it regularly even here in Melbourne. (to complicate the matter, the second biggest killer of Melos is cold weather and overwatering, as they also happen to be rather rot-prone, you should bring them inside or at the very least place them undercover, especially mature specimens with cephaliums).

Some good advice there lewis.

A question regarding overwintering Melocactus sp. as I only have one I know little about their cultivation. I have read that they can perish if the temp falls below 10°C.

So if my temps fall below 10°C (which they already have been, not every day but it will be soon), should I water and pray it doesn't perish, I am determined to keep it alive as I really like the genus. How much water would you suggest over a 4 month winter period? (I realise winter is only 3 months, my winters are a bit extended).

On Mexican cacti, while I still occasionally get 18°C
or 19°C 'rarely' as a maximum, overall the temps are less and I have stopped watering and am sending most of my cacti into an early dormancy (It's nearly winter anyhow). I will not be watering any of my Arios or Astros until spring. Unless I decide to bring indoors an implement a heating statedgy (unlikely). I heard recently that Arios will take up to a year without having water, while I am sure this is not desirable, especially fo root stucture, it gives you an idea of what these slow growing cacti can tolerate.

Melocactus: I have one that has sat outside in 5 degrees C temps over winter for years and had winter rains. Moved house and have a green house, and it cant get rain, unless I water it, which I do. Its still flowering.

Lewis, impressed that you have nudums still flowering.

What is your view on mexican seedlings - let them go dormant / dry / no misting at only 7 months old? I have been misting them, and its getting cold.

Calycium, i don't doubt for a second that a melocactus can take 5C over winter and experiencing winter rain!! In fact, last winter, one of my melo azureus (supposedly one of least cold-tolerant species) survived a 0C frost with ice ON IT, with no visible damage whatsoever. i could not believe it. to this day its fine. obviously i do not recommend this!!
Certainly your plant will enjoy the greenhouse conditions much more.
I overwinter all mine outside under the cover of a small greenhouse. If you get really worried about your pride and joys, bring them inside next to a window. evenbetter in a heated room. This is a highly favoured method used in colder regions of europe etc. also very suitable for Discocactus sp. and Uebelmannias, which hate temps below 15C (whoops, that reminds me, i have a small seedling of u.pectinifera outside undercover and its about 7C .geez i hope thats a myth as well. it was absolutely freezing today) *goes outside to bring Uebie out of cold*

Trigonus,
i have read that to, both in books and online. some sources even say 12-15C. this a common myth.i believe that it is recommended that in the best interest for your Melocactus's health that temperatures do not fall below 10C for any length of time. best interest but not essential. man, mine have been outside all the time up til now and its recently got down to 5C at night. (from now on they are staying inside for the night. lol) to successfully overwinter it, just lightly mist spray it, preferably on warmer (if they exist) days and in the morning so it can dry out during the day. some people claim once a month in winter, i do much more but only very small amounts per day. and not if a 7-C night is predicted. do NOT overdo it, especially, as is likely, cold and wet weather is forecast. how much over a 4 month winter period? that depends. does it have a cephalium? if so that complicates matters. (much less hardy and much easier to kill) what kind of pot is it in? a porous clay pot will dry out much faster than a plastic one.

as the topic of Melos, i got one today, with a parodia leninghausia hitchhiker from a garden centre of all places. steal of a price to. never would have guessed to see a mature Melocactus specimen with cephalium alongside begonias in your average non specialist nursery! its rather large, massive compared to my M. matanzanus which at about 8cm already has a cephalium. its about 25-30cms across, could be pretty old. i will post some pics in a sec when my pc stops freezing k.

I have several large melocactus admittedly under cover of a carport with an iron roof with only protection of the side of the house they are pots that sit on the ground. I water the probably every 4 to 6 weeks in winter and the frosts we have here like last year -3C they did not bat an eye lid. My friends have a couple in the garden with no protection at all and I noticed one today looking very healthy. They get any rain and do fine with this as with their whole collection. I do wonder do cacti actually acclimatize to our conditions. Copiapoas are another that are reported to not take cool temps but I have not lost one yet in winter.

Misting with cacti was talked about at the Succulenticon it was mentioned in a couple of presentations that cacti in winter actual have mist and fogs rolling over them. In Bolivia with sulcorebutia etc lichen grows on the cacti and for lichen to grow they need lots of constant moisture. I am talking about huge clumps that will be eventually over taken by the lichen. I saw some incredible pictures. Another place was the Island of Socotran lichen is evident over most of the island. It rains normally in Oct/Dec with 4" of rain in the wet season then Jan/March 1" of rain the rest of the year it is dry. How do the plants survive thick mist/fogs. Socotran does not get winter but it is interesting to hear how they survive.

It has got me interested in how much can we water cacti, do they really go dormant / do we force them to go dormant / or do they seem to be dormant. I really don't know. Cacti in hothouses would be at higher humidity thus getting some sort of moisture during winter.

I know we can do all the reading we like but there are no books written specifically for Australian growing conditions. I did ask Rudolf Shultz once if he knew of a book and he said that he had thought of writing one but did not think the demand would be great enough for such a book. How sad I was to hear that.

Calycium we have similar winters, I have mamms that flower late winter so would they flower without water. Very interesting subject.

Lewis, go check out my personal photos on this site - have a look at my Melo Azureus with seed

Thanks for the advice - still NOT sure exactly what to do with all my other seed, leave dry / water ... its all so hard. Have already lost some VERY expensive seedlings from watering in the cool.
Misting is not the same as watering...

Thanks Betty,
good to hear your views.

It's not such a big deal if I could just leave them all alone knowing that they are fine over winter - but to not do anything and see them die would be bad - worse for the 200 seedlings I have planted that I want to enjoy next season.

I'm leaning towards light morning sprays of the seedlings every few days, letting the mexican plants go dormant, and watering my melos. Not enough to shock them with water, not enough to starve them of potential growth.

Still got to ask myself the question - do they grow even a tiny bit in winter or go dormant. Good question Betty, Is it induced from what we do, or what we don't do?

how advanced are the seedlings? if they are young and you don't have a heated propagator then i make a strong recommendation. then its always summer, your plants grow continuously and theres no worries! although more advanced seedlings should be treated like normal cacti and given at least some form of winter rest, perhaps a reduced period from that given to mature plants though.

also, where are the melo pics? can't seem to find em, but im obviosuly not looking hard enough lol.

edit: if you have a very large quantity of seedlings then obviously a heated prop. would be impractical.

calycium wrote:

Still got to ask myself the question - do they grow even a tiny bit in winter or go dormant. Good question Betty, Is it induced from what we do, or what we don't do?

seedlings or melos? Like Betty, i have mammillarias. namely carmenae and plumosa, that flower in mid and late winter with no water whatsoever. also some turbinicarpus sp. have been known to give it a shot in late winter. whether they actually do any growth though i'm undecided.
also, if a plant is being un-cooperative (like my nudum) you can always be mean and induce dormancy but stopping watering. cacti are built to withstand drought and will shutdown with prolonged periods of no water.
(sorry, i will post pics of my new melo asap, my pc isn't working that well now).

Lewis your a.nudum isn't being un-cooperative All plants will go dormant when they are ready. I have many plants they have gone dormant and some they are still flowering. Why try and force something on a plant when its not ready. Its the warm spell we had they made it flower. My friends have ferocactus, astro's, coryphantha, cereus and others all still flowering. They sit back and enjoy them and being in the elements they all get rain during winter.

Maybe that is why their plants all ways seem so healthy and grow so much during the growing periods

Who knows................

yep. good point. They will all go to sleep when they feel like it i guess. some just want to stay up late

lewis wrote:

yep. good point. They will all go to sleep when they feel like it i guess. some just want to stay up late

good thread, I have been wondering the same thing...

some of my Mexicans are a little spongy (haven't watered them for a while) but still look pretty awake maybe a little mist before the winter relay settles in?

Yeah,
some of my mexicans are a bit spongey too San - I gave them a water today.