A Noob story and questions

[aklaum]

Hello all,

I wanted to share the story of our entrance into the cactus world and hopefully fill in some gaps in my knowledge.

A few weeks ago my son came home from school and came straight up to my office. With a very serious look on his face he said "Dad, I want to take care of a cactus". He said it with such conviction that we went out that night to a big box store to find some. What we found was somewhat of a cactus concentration camp. My son got quite emotional about the condition of the cacti at that store. He even started to berate the checkout girl about the condition of the cacti. I gently advised him that it wasn't her fault

He picked a somewhat healthy looking Mammilaria hahniana and I picked a Pilosocerus gounellei that someone had knocked off of the shelf out of its pot onto the floor.

Not knowing any better we just grabbed a bag of Miracle-Gro cactus mix, some new pots (which are probably too big) and headed home.

We repotted both immediately with just the cactus mix neglecting to free the roots from the peat they were encased in. We then watered both immediately and put them in their final location. It was about that time that we realized we had no idea what we were doing and started researching. Fast forward to now and we have bought a moisture meter, found cactiguide.com and purchased "The Cactus Family" book and watched many many Youtube videos.

At this point I know our repotting procedure was wrong and that the soil is wrong. We also know, much to my son's consternation, that the flowers on both were fake and hot glued on (these have been removed) We are only watering them when the moisture meter reads bone dry at the bottom of the pot. I have been advised that since it is the end of the growing season, we should not repot into correct soil but leave them until spring.

So, I still have questions.

1. Here in Northeast U.S. what exactly is the growing season? How do we know when to start treating them as dormant and when to wake them up again?

2. My understanding is that we should find a consistently cool, but not freezing place, to put them while dormant. My location choices for wintering are below, which would be best?

Garage - attached but not heated, never goes below freezing
Attic - not heated, never goes below freezing, but can get quite hot on sunny days even in winter
Basement - cool and dry, but rarely goes below 60 degrees
Detached Shed - unheated, will definitely go below freezing with the outside temps
Sun Porch - unheated, doesn't really go below freezing, but can still get quite warm even in winter

3. My understanding is that we should not water them at all during dormancy and that the soil should be completely dry before we move them to their wintering location. Is that correct?

4. I have read some conflicting ideas on whether or not they should get sun while they are dormant. Some say that giving them light will make the transition back to full sunlight in the spring easier. Others seem to winter in complete darkness. Which is best?

5. We are going to stick to indoor cacti for the foreseeable future. I'm trying to figure out the best location in our home to put them during the growing season. My choices are:

Southwest Facing windows - These get indirect sun all day and direct sun for a few hours late in the day. Our window sills are quite small so we would have to build something if our collection grows.
Northeast facing bay window - This has a lot of room for plants, but is under an overhang and almost never gets direct sun
Southwest Facing "greenhouse" window - This is basically a box window that was added onto our kitchen window. It gets direct sun most of the day but can get quite hot.
Southwest Facing Sun Porch - it has no AC so it can get quite hot in summer

6. We would like to rescue more cacti from the big box stores and maybe look at some online. At this point in the season should we just bring them home, let the soil dry out, and put them in the wintering location until spring?

I think that's all for now. Thanks for indulging my long post if you got this far

[iann]

If they really are dormant then they won't grow, so they don't strictly need light. Keeping them in the dark does make the more sensitive when they first come out into the sun. Dormancy requires consistent coolness. Sufficiently warm days, even with nights close to freezing, is good growing conditions for many species.

If they really are dormant then they need very little water, but possibly not none. Indoors in heated conditions can be extremely dry in winter, which dries out even a cactus. Don't worry about a little shrinking and wrinkling, but if they go too far, or columnars start to get floppy, then maybe a bit of a drink and a few days in the warm. Mostly you can treat them as paperweights during winter. Even new rescues aren't likely to die in their peat coffins until you try to water them in spring.

Difficult to find the right spot indoors. A sunny window is almost a necessity, the more sun the better. Getting hot will usually be more of a benefit than a problem, but you'll have to feel your way because it is perfectly possible to overheat even a cactus.

[greenknight]

Welcome, aklaum! Great that you're making the effort to learn the right way to care for your cacti. Sounds like your son has the makings of a real cactus aficionado (I've never chewed out a store clerk over the condition of their cacti, but I know the feeling!)

I'll try to tackle your questions in order:

1. Hold off on watering after the first day of Autumn. If conditions are cool enough you can keep the cacti completely dry, if it's a too warm you may need to give a little water, but no deep watering until weather warms in the Spring. Around the first day of Spring it's time to think about giving them a good drink, but wait for a spell of good weather.

2. Not all cacti need a cold winter rest, some are tropical. Pilosocerus gounellei comes from the caatinga region of Brazil, where there are only two seasons - wet and dry. both hot. It's going to get too large to move easily anyway, I'd put it on the sun porch and leave it there. You could probably do the same with most cacti, if it doesn't get too extremely warm. Many cacti will bloom better if wintered cold, for those the garage sounds like the most likely spot. All cacti are not the same, find out what conditions each species needs.

3. See answer #1.

4. You've pretty much got it - it's better to have light where the cacti winter, but not crucial. For those species that need cool conditions, that's more important, even if they're in the dark - but expose them to sunlight gradually when you bring them out.

5. As I said earlier, all cacti are not the same. Some like direct sun, some need a lightly shaded position. You're fortunate to have a range of different conditions available. The sun porch should be good for most, though, assuming it has some provision for ventilation.

6. You can repot during the dormant season, just don't water after potting. Peat is impossible to remove when it's dried out, without major root damage - if they're wet I'd repot immmediately, if already dry you might as well wait until Spring. Online sellers usually ship cactus plants bare root, you'd want to pot them up right away. This is actually a good time to buy online, before the cold weather sets in and makes shipping them dangerous.

I bought a couple cacti online last Fall, potted them up and left them alone until Spring. They both did great. One, a Gymnocalycium anisitsii ssp. damsii, arrived with flower buds already on it which proceeded to bloom as soon as the weather got warm. (It loves heat, would be a great species for the "greenhouse window").

I hope that answers your requirements, and I wish you all success in your cactus growing.

I see that ian has posted while I was composing this, with words of wisdom as usual.

[aklaum]

Thank you both for your valuable information. So if I'm reading everything right, the ideal wintering procedure would be:

Pilosocereus gounelli

Allow it to completely dry out starting now
Keep it in the house as it does not really need cool temps to go dormant
Keep it in a place with at least some light (southwest window?)
Watch for signs of severe dehydration but otherwise leave it alone

Mammillaria hahniana

Allow it to completely dry out starting now
Keep it somewhere consistently cool (garage?)
Keep it in a place with at least some light (garage window?)
Watch for signs of severe dehydration but otherwise leave it alone

I think I'm going to buy one of these for my old smartphone and try and track some temps in my various indoor locations to see how cool or how hot they really get.

http://thermodo.com/" onclick="window.open(this.href);return false;

What about Stenocactus multicostatus? Same treatment as Mammillaria hahniana?

greenknight, both cacti are already almost bone dry so I think I'll hold of on repotting until the spring.

I guess the final question is, what does a cactaholic do all winter while the cacti are sleeping?

[george76904]

Thank you both for your valuable information. So if I'm reading everything right, the ideal wintering procedure would be:

Pilosocereus gounelli

Allow it to completely dry out starting now
Keep it in the house as it does not really need cool temps to go dormant
Keep it in a place with at least some light (southwest window?)
Watch for signs of severe dehydration but otherwise leave it alone

Mammillaria hahniana

Allow it to completely dry out starting now
Keep it somewhere consistently cool (garage?)
Keep it in a place with at least some light (garage window?)
Watch for signs of severe dehydration but otherwise leave it alone

I think I'm going to buy one of these for my old smartphone and try and track some temps in my various indoor locations to see how cool or how hot they really get.

http://thermodo.com/" onclick="window.open(this.href);return false;

What about Stenocactus multicostatus? Same treatment as Mammillaria hahniana?

greenknight, both cacti are already almost bone dry so I think I'll hold of on repotting until the spring.

I guess the final question is, what does a cactaholic do all winter while the cacti are sleeping?

Work on next springs want list!!! Congratulations on your new addiction. Forget what you thought previously you will spend significantly more than you ever planned and be thrilled you did . The flowers and even the plants themselves are so stunning and strange. I started last December growing some saguaros from seed... Now I have "lots" of cacti. With many more planned for next year. I already have plans for a new 10x12 greenhouse. Look at me I can't wait for spring and its barely fall... Oh well, guess I'm off to work more on the wish list. Good luck on the new plants.
Will

[greenknight]

Stenocactus multicostatus I would winter in the garage.

What I meant to say was: if you rescue any more from big box stores, repot them immediately if they're wet. Hard to get peat to absorb water once it's dried out, plus they'll be safer out of that wet peat.

[graffiti]

I don't have any real advice as I'm just learning to (properly) care for my cacti. That said, this line caught my eye:

We also know, much to my son's consternation, that the flowers on both were fake and hot glued on (these have been removed)

Your son is in for something much better as he learns to grow these (and potentially other) plants correctly. Both the Stenocactus and the Mammillaria will be quite pretty when they flower next year. Don't worry too much about the soil. They should be fine as long as you don't over water.

Come spring, go to NAPA (assuming you have a NAPA around you, if you're in New England) and ask for part #8822, calcined diatomaceous earth. It's sold as a oil absorbent, but in CT, it's my basis for my cactus soil. It's also a large part of all my potting mixes as it promotes good drainage.

If you're in southern new england and want to kill some time, think about visiting Logees Greenhouse in Killingly Ct or Peckhams in Little Compton, RI.

[aklaum]

Thanks for the warm welcomes and advice. This leads me to another question. Come springtime should we repot them first thing or let them wake up and get acclimated first?

[graffiti]

According to a learned member here, you can actually unpot your cacti for the winter if you keep them cool enough. So I'd say that you can do it right before the growing season starts and be fine.

[SoilSifter]

Carefully watch the cacti as Spring nears. If they start growing in light that is too low then they'll become etiolated. Unfortunately the etiolated section of growth never fills in to look like the normal parts of the cactus after giving the plant enough light. I have a couple cacti that have this problem.