Just a thought on the cultivation of drosera...

[Vertigo]

A lot of Drosera species seem to need a high amount of light to really do well, along with this they also seem to need high humidity.

In keeping various Drosera i've noticed that for a short period of time, a Drosera completely enclosed, with 100% humidity, and high light will thrive, and look absolutely stunning...for about a week or so. At this point fungus among other things settle in and the plant starts to decline.

It seems that air circulation amongst the sticky tendrils and high humidity is a definate must for Drosera in cultivation.

For instance...I was growing Drosera falconeri and paradoxa last summer under glass in direct sunlight for most of the day, the glass container easily fit three 4.5" pots inside. One of the spaces I used for a container of water to insure high humidity...the plants did not sit in trays.

This year I am trying the same growing conditions, only in a more confined space, only enough room for one pot, with a little space around. I'm finding that there is just not enough space left for a constant source of non-stagnant air, and I am seeing a decline in the plant. With less air circulation the substrate in the pots also tends to stay moist longer, which could attribute to rot/fungus.

There are definately many factors it seems to take into consideration when devising a grow space for Drosera. Many more than i've seen with other genus. Usually there is a trade off, more light for a little less humidity...etc...as far as Drosera though, so far they definately seem to know what they like and usually won't settle for less. I guess that's where we come in.

 

[Tamlin Dawnstar]

All Drosera prefer outdoor conditions where air circulates.  Terrairum grown plants are weak, and very susceptible to fungal infections.

My own method is to grow on racks with a thin sheet of plastic suspended in front when I am not with the plants.  In the spring, each morning the flats go outside on staging.  The humidity averages 40-70% and the plants need protection only on the days where humidity is below 40%, when there warm drying winds, and crystal clear skies with full sun all day.  AT night, they come back inside under lights where the humidity is higher.  So, they get the best of both worlds.  The higher humidity at night gets them really dewey.  I keep close watch through May on the plants, as they haven't the deep protective coloration yet, but by June the plants can take full sun as if they were cacti.  They stay dewey.

Alternatively, I have also grown them in a deep bin, with drainage.  The bin sat in a wheelbarrow full of water.  The bin was planted with very young seedlings, and these were pre acclimated to sull sun.  Plants matured and flowered the same season.  They were occasionally underwater for days after rains.  A sheet of glass covered the top of the bin leaving 1/4 inch for air circulation.  The whole sat in full sun.  I would have expected the plants to bake to mush, but they throve like no other Drosera I have grown.  The small clearence space between the top of the sunstrate and the glass was no more than 3 inches.  These plants were thick, thrifty and strong as nails.  Nothing fazed them.  Included in the experiment were some alpine species of D. spatulata.  I grew D. aliciae, binata, coccicaulis, dielsiana, intermedia, ericksoniae x pulchella, capensis, spatulata Ahipara, nidiformis all with resounding success.

I guess my point is that the plants are very adaptable if you move slowly, in stages of hardening them off to more harsh conditions.  An added benefit of getting them out of the tank and into the outdoors if at all possible is the plants build the reserves they need to survive the less hospitable winter conditions when grown in this manner.  This is known as maximizing the homeostasis.  The life force of Drosera are like batteries.  If you run the batteries down, the result will be weak, dewlwss plants easily prey to insects and fungi.  Keep the batteries charged dby providing optimal light and other growing considerations, and you charge them up.

Drosera look delicate, but thay are tough plants as long as you dont fry them by trying too much too fast.

 

[Jason Wong]

Dangit, that explains why mine always catches a fungus...any suggestions for increasing air circulation, Tamlin? Might get a fan or air-con...

 

[Tamlin Dawnstar]

Jason,

Why do you feel you need a terrarium? The best way to increase the air circulation is to have the plants in open air. I realize that this isn't always possible, but with a relative humdity above 40% many Drosera species will do just fine.

Here in the spring there are plentiful rains, and humidity is usually between 50-80%. I have my plants outside in the full sun (49% available sunlight here so I give them all I can). They do very well like this. In apartments, with air conditioning removing the humidity from the air, there might be some potential problems. I have no experience with what is possible or not in air conditioned situations, and I presume you are growing your plants indoors and in terraria. Probably increasing your light wiould help make stronger more fungus resistant plants.

If you can grow Sarracenia and Dionaea without a terrarium, the Drosera species would probably do fine. An added benefit of getting the plants more out in the open is the available light from your light tubes will have its full possible effect instead of being screened out by the glass of the tank.

I know how rare carnivorous plants are in your area and how hard they are to come by, and it's hard to risk a beloved plant, but some experimentation would be a good idea. Starting seedlings right out in the conditions you want to grow them in is always a good plan since you are selecting for individuals with a greater tolerance for lower humidity.

 

[jimscott]

I can vouch for lower humidities and AC. The plants that are not outside are in the lab's relatively dry air. They DO sit in containers of water and get replenished a few times a week. They are by southwestern facing window sills and very dewy. They glisten in the late afternoon and early evening. My capensis, intermedia, anglica, and sandersonii are all blooming under these conditions. Pics are forthcoming. Fair warning! (640 X 480). The only plants I cover are seeds, fresh seedlings, and the occasional "in shock" plant. The approach works. Tamlin and Schloaty are entirely correct.

 

[Zongyi_Yang]

i found that one way to increase air circulation is to have a acquarium fish pump (or two) pumping air into your tank with tubes. the air entering isn't too much, and should not effect humidity by too much. but the air is moving, and can be directed around or at your plant. i use this with my neps. Zongyi

 

[Vertigo]

Quote[/b] (Zongyi_Yang @ May 25 2004,5:08)]i found that one way to increase air circulation is to have a acquarium fish pump (or two) pumping air into your tank with tubes. the air entering isn't too much, and should not effect humidity by too much. but the air is moving, and can be directed around or at your plant. i use this with my neps. Zongyi

You wouldn't have to worry at all about humidity if you put an airstone on the end of the tube and set it in a container of water. You'd have the best of both worlds there.

But Tamlin is definately right, open aired growing (plants willing) is really the healthiest way for the plant to grow. I mean, they're more than carnivours, they're plants as well. And all plants need fresh air.

Plus, if you use the tray method, the humidity around the pots and at the substrate level is usually much higher.

 

[Khoas]

I grow all my tuberous and pygmy sundew outdoors. I find they don't like the warmer temperature and lack of air movement that occurs in the greenhouse. Anyone try to grow Pinguicula outdoors?

 

[Jason Wong]

Quote[/b] (Zongyi_Yang @ May 25 2004,11:08)]i found that one way to increase air circulation is to have a acquarium fish pump (or two) pumping air into your tank with tubes. the air entering isn't too much, and should not effect humidity by too much. but the air is moving, and can be directed around or at your plant. i use this with my neps. Zongyi

Exactly what I did...but they don't pump much air when taken out of water, and the vibrations produced when pumped the air into the water below my terrarium sent out vibrations that made the traps on my VFT go DOWN about half an inch or so...or maybe that was due to my care

I use misters for my neps, to simulate their humid environment
(mist is soooo cool, really adds a hint of graceful glamour to a terrarium...

)

Tamlin, I grow my cps in a terrarium becuz I don't have a garden, and my motehr would probably ditch them if she saw them lying on the floor or just on stands (the terrarium is just for enclosement + tidyness, nothing much else

I'm just starting to order from overseas now, to avoid the monopolistic prices of cp retailers around here...

BWT I find the emoticons way TOO expressive, since I like to remain in the dark a little...

See what I mean?

 

[Jason Wong]

Besides I'm not sure whether the air pump would spoil, being taken out of water, have to check up on that one...

 

[The Griffin]

You wouldn't have to worry at all about humidity if you put an airstone on the end of the tube and set it in a container of water. You'd have the best of both worlds there.

Hey Vertigo,

I had this idea also, but mostly for neps. Has anyone tried it? I thought it would have a smidgen of cooling properties too if done at night.

Joe

 

[Zongyi_Yang]

hmm, i have one of those silent pumps that dosn't really create any vibrations. ive been using it for a while how, and i dont seem to have faced any problems with it out of the water. i too use it with a mister so that it circulates the air. i dont use an airstone as it kinda makes it less effective (unless you want to put it under water). Zongyi
P. S. i agree that these smilies are too expressive. they really scare me...