Humidity 101

Over the last 3 years I have become acutely aware of the effect of humidity on begonias (and other tropicals to a lesser extent). Begonias flourish inside a terrarium (fish tanks for the most part plus other glass bowls) but they can become costly if you housed hundreds of begonias in tanks. I've experimented with plastic baggies, humidity domes (these are good if you have the tray that matches for a good seal), and other various plastic bowls, cups, lids, etc.

I wish I had taken pictures of some of my poor looking begonias before I resorted to covers recently. Due to the overwhelming success with almost any kind of humidity cover, I have resorted to covering every (poor looking) begonia with something. For small pots, plastic drinking cups (I have the 9 and 16 oz cups from one of those wholesale places where they come in 100 and 200 packages for less than $10) have proved very handy. The one thing I have to pay attention to is mold since it loves these conditions. Some rhizomes and canes are bigger than the cup as well but I try to cover as much as possible even if that means that part of the rhizomes are sticking out or the cane is supporting the cup instead of the surrounding soil.

Anyway here is evidence of a sort. In this photo are two starts of hatacoa 'Silver' with a cup in place. The hatacoa on the outside looks healthy with the puckered leaf but two leaves have already been cut off due to dryness.

Here is the evidence with the cup removed. I put a skewer behind the big plant to hold the leaf up. That is a downside of using cups - you must force the plant into a smaller space - but what a difference.

Just had a thought Butch, what about using those quart deli containers that are clear. They are wider than the Solo cups.
And you are so right. Most begonias do better with humidity.

Here is the high humidity dome. It doesn't seal well with the Permanest tray but it beats a snowball. The plant in front is 'Midnight Sun'.

Laurie, I use everything I can get my hands on. Here are sponge cake lids (not only do you get your cake but you get to eat it plus use the lid).

This is taliensis, diadema (in the back supporting the lid cockeyed), and I think 'Persian Brocade' on the left that I was close to losing until I took drastic action (same thing happened last year to it).

My big utility room needs lots of humidity control since there are two furnaces in this room. While not hot in there, it does suck the moisture out of the air.

This is 'Mo Reese'. It was half the size over a month ago. I put a container over it about that time. Here it is with lid. I'm too lazy to remove the labels (they should be a lot easier to remove).

'Mo Reese' without the lid.

Here is the perfect environment.

You are so right! I have found especially down here in Texas that the only way I can grow a begonia is inside an aquarium. Outside is too hot in summer, and combine that with our insanely salty water....I lost most all of the ones I moved here from Ohio. Made me swear off begonias, but of course that didn't last too long. I am now back in the game with a few I have purchased the last couple months. The canes seem ok right now in a northeast window, but the rhizomatous and rexes went straight into the aquarium. They are doing well right now....keeping my fingers crossed. I also use the aquariums as propagators, with a germination mat underneath...works well in the winter for hoyas at least. I also find that my couple episcias will only thrive in the aquariums.

Kim

Kim,

I would've thought TX would've been a great place for begonias (check the ABASTRO site). Maybe you are in the more arid part of Texas.

I have one episcia and it is about to take over half of the big aquarium in the above picture (the other side not shown).

Aquariums are great for propagating especially for saving any plants that are close to death (I saved 'Chivalry' with a couple of leaves this way, not once, but twice). That brings up the other thing about these ideal conditions - if you start a plant in a terrarium do not pull it out after you get it going and expose it back to the same conditions that put it into a downward spiral in the first place - you will kill it this way. I did this over a year ago with several begonias. They were growing so fast that they were crowding out each other. I pulled the most robust ones out and lost them all in a matter of a few weeks. Lesson learned.

Here is that old tank - most of these were started with a leaf. 'Purple Snow' and 'Deco Deviltry' were fighting for space on the left. The right hand corner was some kind of bowerae ('Kit Kat' or 'Tiger Kitten' whose leaves were 3 to 4 times larger than normal). 'Marmaduke' was doing great. What is not shown is 'Chivalry' and another 'Purple Snow' in the left hand corners. I was able to salvage the last two leaves of 'Chivalry' and save it.

Yea....I thought so too. The humidity is great, but the heat I think did them in. I had them outside and one by one, the leaves browned and fell off. It could also have been our water, which is really salty here. This year I will be trying them under a shade cloth watered with rain water to see if it makes a difference. But I am taking cuttings prior to doing that as a precaution!

:) Kim

Good idea to have some extras for a little insurance. What are you watering with indoors?

I used to go around to all my potted plants with a watering wand which took an hour or more a day. Last summer I set up several hoses on a multiple timer and watered most of all my potted plants 45 minutes 3 days a week. I messed up and turned off a valve to the ones on the front porch before we left for two weeks in July. Most of the begonias survived but some other potted plants did not. All the ones in the backyard did great.

Right now the few I have indoors I have been watering with our water, but minimally since they are in the aquarium and stay moist. Doesn't seem to be hurting them too much yet. I want to set up a small system to collect rain water outside, but haven't had time to do this yet. And my budget doesn't allow for the purchase of special water for plants....lol. I'm thinking some drainage pipe or a small gutter leading down to a tub will work for me for the collection. Nothing fancy, and since I am renting nothing too permanent either. Funny thing is my hoyas could care less what water they get it seems. They never blinked at the high salt.

:) Kim

I know some people swear by rain water but that would be a tall order for me. I probably use 40 to 60 gallons a week for winter needs. I try to fill several containers at once and let them sit for a day but sometimes it's right from the tap to the plant.

My mother uses water collected from the dehumidifier but for a few plants this is fine. Their water also seems like they have a lot more chlorine than we do.

What do you use for drinking and bath water? I know a lot of coastal towns have what smells like sulfur water but I've never noticed a salty taste.

I grew many kinds of Rex Begonias for a number of years, and pretty much the only way that I had great success with them was growing the plants in aquariums and bell jars. I finally gave it up though because after awhile the moisture would invariably etch the glass and turn it milky looking. It became so unsightly that I eventually gave up on it and threw out the aquariums. It is funny, but I still have a few of the begonia's left from their "glass house" days (Shamus, Pink Surprise, and a couple of others that I can't remember the names) and stuck them in an old plastic window box, put them in a North Window at work, and they look great. It is hard to understand, because with central heating here in VT, there is literally almost no humidity in the air; it is like the Sahara in this building. The only reason I can think of for this success is that the large plants all being in the same container must provide a micro climate for themselves by being so close together. I need to take a picture and post it, because it truly looks spectactular.

How many years did you have your aquariums? It sounds like some serious acid etching to turn glass milky white. I've seen that on double paned windows where the seal breaks and the cycle of evaporation and condensation leaves mineral deposits on the inner side of the panes which makes them useless. You should be able to scrape deposits with a razor blade.

I have found that the very few begonias (3 to 4) that always stay indoors (and those are the ones that aren't in the basement) have turned out to do just fine without anything extra. I assume this is just from conditioning. The ones that stay in the basement are the ones in aquariums and do fine as well. The rest of them go outdoors from April to November but suffer terribly once moved back indoors for the winter. Extra humidity seems to be the best solution for the majority of rhizomatous types (that includes rexes).

Here is 'Shamus' that stays indoors year round because it is growing in (and now is growing over and out) of a glass bowl. I wish all of them did this well.

I kept the begonias in glass containers for about 3 years. I mostly used 10 gallon aquariums, but I also had a 50 gallon (36 inches X 18 inches X 18 inches) that I used for about a year. Besides the etching problem, I had these tanks in my living room and they just were not very appealing to look at. Also, I had the plants planted directly in the tanks (peat based potting soil over gravel) and when I needed to start the whole thing over again, because everything was overgrown, it simply became too much of a chore. Ninety percent of my house plants are now Hoya, because they are so darn easy, but I still have a soft spot for Begonias especially well grown specimens. By the way, great picture of your Shamus growing in a bowl!

If this comes out (this is my first attempt at posting a picture), this is a photo of the inside of one of my "Begonia tanks" from 2004. Notice the moisture on the glass.

I guess that's part of the reason I have been staying away from begonias now too, the aquariums aren't pretty and take up a lot of room. Not to mention if I need to move again, yikes. I have mainly hoyas too. Maybe we can do some trading when it warms up for you.

:) Kim

I didn't have any begonias until a friend handed me a very poor looking one to take home with me. I knew nothing of them to be honest and I really didn't like them. BUT... that has since changed. I put it inside of my green house through the winter where it bloomed and bloomed and GREW!!! It's at least 3 times as big as it was when I got it. I plan to take cuttings off it and try to start new ones. And repot the original plant of course.

It's worthy to note that the humidity in my green house is higher than outside. But I don't let it stay too high as to create fungal problems and such with my other plants.

I don't know if the begonia puts out seed, I've seen no signs of any... but I could be wrong. It's just a standard single red begonia.

For the cuttings, my intention is to dip cuttings in rooting hormone, put into a small pot and cover with a sandwich baggy... then gradually acclamate to regular environment by increasing the time without the baggy (starting with slightly opening the baggy on one side). This is the way I have done most of my cuttings and I must say... it really works. So humidity is key. The baggies fog up, so I know the humidity is high... but that seems to make rooting very easy.

I know I have digressed here... sorry. But any other help/tips with this plant would be appreciated. I've just been treating it like I do my impatiens... only this plant seems to be much stronger.

Take care,
Donna

Edited to note: I keep all my rooting cuttings in the shade.

This message was edited Feb 25, 2007 12:21 PM

Hoya,

Looks like you have some great looking begonias in that tank. Condensation is part of the cycle but again I haven't noticed any etching (maybe where the soil comes in contact). Maybe you should try some dwarf begonias if you don't want to change your tanks out every year?

I have 3 ten gallon, a 30 gallon, a 60 gallon, and a 120 gallon tank plus several glass bowls, candy dishes, cookie jars, etc. The big one requires two people to move it. It is 4 foot long, 2 foot high, and 2 foot deep. Everything grows to perfection in these kinds of environments but you must remove fallen leaves to prevent a lot of fungal problems.

Again, I wish I could afford more big tanks or even better a terrarium that covered one wall - say 20 foot long by 4 foot deep and 8 foot high. Wow!

Donna,

You don't really need to dip your begonia cuttings in rooting hormone but it doesn't hurt either. Humidity is definitely a key ingredient to begonia propagation. Sounds like you already have it figured out doing other plants this way. One way I have done it in the past is with those disposable lasagna trays with the plastic lids.

Most Begonias are not difficult to successfully pollinate, provided that some male and female flowers are open at the same time.
Some species even set seeds without pollination (i.e. Begonia subvillosa), but to be sure, you should play the bee's role yourself.

Growing from seed requires some experience though, even if it's far easier than with orchids.
They will come true to the parent if
- it is a species
- the cultivar is bred and selected over several generations (i.e. many semperflorens hybrids)

Most cultivars' seeds will result in a wide range of different youngsters, that may express any number of the involved parents' features.

I keep telling people about the plastic humidity tents for big gro-light stands from Charley's greenhouses for 49.00. They even have a zipper on either side to control the humidity you want. I am verrrry impressed with what they do for me. Last night I brought in 3 gallons of Esperanaza that had not gotten planted before the bad weather came in....they are sooo happy where they are now, so I will be able to ship them out in a week on trades..I will take a pic and show you how happy the nex rex begonias are, too in this environment.
Charley's makes different sizes of these tents....my gro light stands are 72" tall....

Hi bettygail,

I like your setup. I have the same shelving and just went to Charley's greenhouse to see about that cover, but couldn't find it. Do you know what catagory it was under? Also, where did you get your light units?

Thanks.

While the humidity cover that Betty is showing from Charley's looks great, at $50 apiece, I'm willing to continue my hunt for cheaper alternatives. I have ten shelves now plus 5 wood shelves that are twice the size of the chrome shelves. So that would be around $1000 to buy these to cover all my shelves.

CTMGGardener....I will find it....it was hard for other people to find to buy and eventually I called and got the number to type in for search.....it is here somewhere and I will come back to you

CTMGGardener...you have dmail
and hcmcdole....these have made me not want to build the greenhouse from Charleys yet.....these are serving me well as real greenhouses..... this sure beats almost 10,000.00 for a good greenhouse!!! I am going to continue building the stands....
I am scatterbrained....sorry....forgot to tell CTMG that my stands came from Sam's for 100.00 each with rollers. The shop lights came from Lowe's as did the gro lights....you want to be sure and get the shop light fixtures as they have the hood to direct the light down....

IGS also carries tents for light carts, not sure if it will fit the costco/sam's club type but you can take a look and see http://indoorgardensupplies.com/clear-vinyl-tent-seedling-carts-lite-carts-p-571.html

thank you begonia lady for options....gail
fantastic and save 10.00 doing it....they have wonderful other items, too....that tent is just like mine, but I didn't look to see if it had zippers which is what I like so much.

This message was edited Feb 25, 2007 8:38 PM

Betty, You paid too much for those stands at Sam's if you paid $100. Ours is around $76. I see that the price does vary depending on the area but +30% more seems high.

http://www.samsclub.com/shopping/navigate.do?dest=5&item=168602

Check out this thread for more information on stands (racks, shelves, etc.) and lights.

http://davesgarden.com/forums/t/683246/

Yes, hcmcdole, our local Costco carries these chrome shelves (They are very nice and industrial - 5 shelves per unit) for about $76 as well. I was very interested to see the clear tents that are available for them. I used one of these tents for a compact light cart from (Indoor Gardening Supply Company) durring my African Violet/Chirita/Streptocarpus phase. I found that on the commercially made light carts (mine had four shelves with four (4) tube fixtures on it) when used with a tent kept way too much heat in the unit. When I kept African violets, they all ended up with powdery mildew, because of lack of air circulation. Even when I kept the front opened up with zippers, it kept too much heat in the unit. It was impossible to ever go away for even two days without everything drying out. I think BettyGail's set up is better than mine, because there are not as many lights to generate as much heat. Also, I never tried mine with Begonias; it may work far better. Anyhow, Bettygail your plants look superb.

Hoya,

Sounds like you had some really hot lights or too many lights. My medium tank (60 gallon) had 4 tubes over it which I kept on 24 hours a day two years ago. I did find it was too hot so I removed two tubes plus have a timer on it now for 15 hours a day. Being sealed in fairly well, I rarely water it and a lot of the begonias and volunteer ferns are touching the top of the cover of the light fixture. The leaves that come to rest on that cover may show some damage so I clip those back from time time.

I'm surprised yours would dry out unless it had some big holes for ventilation or you kept it like a desert.

It would work differently with an aquarium. With my light cart (I have attached a photo of one shelf with some of my Streps), there were 16, 24inch, T12 tubes in total. That is a lot of heat. By cramming four shelves on the unit, the top of each light fixture is only two inches or so below the shelf above it. I simply could not keep up with the watering especially in the winter when it is so dry indoors here in VT. By adding a clear tent to the set up, it only held in more heat making the temperature on each shelf around 95 degrees, which is really kind of hot to maintain plants at. Also the tent made a perfect breeding ground for mold and mildew. If I were to do it over again I would have bought the cart with only 3 shelves - less heat and more growing room for plants on each shelf.

This message was edited Feb 27, 2007 9:43 AM

Can't you take one shelf off? I explained back in the thread (mentioned above) for the 6 foot shelves bought at Sam's (and other places) that six shelves is too many for a plant stand (unless you are growing very low plants or seedlings). Four is ideal but five is managable. I have one shelf that has six shelves and as soon as it warms up and everything goes back outdoors, I will remove one shelf and adjust the rest for next winter. You do need room to grow and manuever.

Why do you mix different length tubes on the same shelf? Maybe you could turn one or two off to reduce heat.

That is one negative point about humidity because it does promote mold and mildew but by cleaning up on a regular schedule, those problems can be minimized or eliminated. I try to remove leaves starting to turn, leaves that have fallen, spray affected stems, and vent if too much humidity is present.

http://davesgarden.com/forums/p.php?pid=3070455

Finally moved my Curly Fireflush and Midnight Sun to a tank. I've had them since the middle of Jan.

Here is the big tank.

Left half of the same tank. The rexes are bright.

Right half of the same tank. Smaller begonias and a sprawling episcia.

This is goegoensis. It was looking pretty sad until I placed a cover over it. Now it is about to push the cover off.