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Darlingtonia Self-watering System + Temp Questions

So it's been a few weeks since I got my Darlingtonia, and I've been trying to figure out a way I can keep my plant in the sunlight all day without it getting overheated. I decided I was going to create a system where I would have a separate, insulated reservoir that would house a small water pump, which would (in theory) pump cool water over the roots of the plant all day. The pump would be solar-powered, so it would only come on when needed... In most of California, heat and lack of sunlight are mutually exclusive, so I'm not sure how this system would work out for those of you in the east where nights are warm too.

My supplies were as follows:

Solar-powered water pump - I used this one
8" plastic pot - this is the main reservoir
Decorative glazed clay pot - for insulating the reservoir pot
Tray for a 10" plastic pot - just happened to fit perfectly as a lid for the 8" pot when turned upside-down
A few feet each of 1/4" and 3/8" clear tubing - you can just use the 1/4" if you want
And of course, my Darlingtonia plant

Assembling this contraption was relatively easy. For the main compartment, I filled the clay pot with water (more insulation), then put the plastic pot inside of that and filled that with distilled water. I then cut a hole in the tray (lid) and fed the tubing and wire through. The 1/4" tubing connects to the output on the pump, and at the end of that tube I attached one of the fountain heads that comes with the pump using a small section of the 3/8" tubing. I also tied a knot in the 1/4" tubing because I found the water output was too strong for this purpose. Then one end of the 3/8" tubing goes in the reservoir pot, and the other into the Darlingtonia's outer pot (you need to remove the air from the tube so water can flow freely between the two vessels). As a final touch, I wrapped the tubes in white duct tape to prevent the water from heating up as it flows from one pot to the other.

This system ran perfectly, but I still have concerns about the water temperature. Today was a relatively warm day with air temperatures in the mid-80s, and I found that by 3:00 pm, the water temperature even in the shaded reservoir (and consequently the plant's roots) was approaching 80°F, so I put some cold water in to cool things off a bit. I know that 27°C/81°F is the critical temperature for Darlingtonia, but I have some questions about what exactly that means. Does that mean that the plant cannot tolerate that temperature at all, and if the roots get that warm you might as well throw the plant away because it won't be able to recover? Or is it possible for the plants to endure relatively brief spikes (say, 1-2 hours) of that temperature or slightly above as long as water is constantly flowing over the roots and it cools off at night? When I check the root temperature in the morning, it is usually 52-54°F.

I've been wondering what it is exactly about the warm root temperatures that kills Darlingtonia. Is it just that the plant physically cannot function at that temperature, similar to how humans die if their body temperature reaches about 108°F? Or is it due to external factors, such as root rot or the lack of oxygen in warmer water? If it is the latter, it seems like having water constantly flowing over the roots would remedy that even if the temperatures are above optimal. My plant is of the Sierra Nevada variety, which is supposed to be more tolerant of blazing sunlight, low humidity, and higher temperatures than the coastal types. Would this make a difference in the hardiness of the plant?

I guess I'll have to wait and see how this goes, but in the mean time I have ice cubes ready to pop in the reservoir if necessary.
I've never had problems with my Darlingtonia in full sun in the San Jose area. I just water every morning with room temperature water; they don't stay sitting in water. All three of mine are growing in live sphagnum. I haven't had problems growing them in 85 degree heat, full sun, and black plastic pots. It may just be that I have 3 "lucky" clones that have persisted for years this way, but I still think that people are over-playing the cool-root hypothesis.

As a test, I set one of my pots into a separate tray, then watered with warm (85 F) water. There were no noticeable side effects of doing this; the plant kept on growing as it had all summer.

I think that the key to growing Darlingtonia is an open media kept moist (not waterlogged) with cooler nights. It's worked for me, anyways. I can test to see if my conditions are favorable for more clones (hint, hint ;)).
Whew, that's good to hear. Do you keep track of the root temperatures of your Darlingtonias? How large are the pots they're kept in? I'd like to think that the fact that the water is constantly flowing over the roots (like in their native habitats) would somewhat offset the heat sensitivity, but I'm just not sure.

With my setup as it is pictured, I think the large pot around the plant's pot might have contributed to the higher temperatures. It seemed like after the water ran through the pot, it would go into the large white pot and just hang out for a while and heat up before going back into the other pot. This in turn heated up the reservoir pot under the stairs when the warm water flowed back into it. After the sun set, I put a few more pieces of slate under the plant's pot to raise it up and consequently lower the water level in it, and I'll see if that helps tomorrow.

Once my plant gets a bit bigger we can trade some clones. :D
My clones are in 2, 4, and 6-inch plastic pots. I don't like to sit them in water, not because it gets hot, but because constantly wet sphagnum can start to stagnate and smell, which isn't very pleasant. I don't monitor the temperature of the soil. It might be quite interesting to run some tests of that sort...
Nice setup. You could probably do without it in your climate but by all reports this species definitely benefits from having water circulation around the roots. I would guess the roots prefer higher levels of oxygen. This would explain why they do better in less compact mixes and why top watering works better than standing water.

You can buy foam sleeves for insulating pipes which would probably be better than duct tape.
My friends in Texas keep the plants in several inches of water and use an inexpensive air-stone to aerate the tub. Simple; cheap; effective. Nice set-up you have there . . .
Oh, and I recall reading in one of the old issues of the Carnivorous Plant Newsletter the critical soil/root temperature for Darlingtonia is 81°F (27°C). As long as you keep the soil/root temperatures below this the plant should survive. Air temperatures can be much higher.
Quite elaborate! Honestly, I have nothing more sophisticated than a planter, on my porch, in direct sunlight:




I just water from overhead when it doesn't rain. Our summers are in the 70's, 80's and low 90's.
Sorry, but totally unnecessary in my opinion. I've repotted darlingtonia where the moss was so hot it was steaming when it was removed from the pot.

Yes, some plants happen to grow near running streams or flowing groundwater, but the majority just grow in meadows without water running over the roots.
  • #10
Well, I think it's brilliant. Nover heard of a solar powered pump before.

  • #12
Back in March I set up an outdoor tray plumbed with a bulkhead and some pvc pipe. The tray sat on a metal frame and under the tray I put a 20g reservoir of water. In the reservoir I put a pond pump and I used drip irrigation equipment to have water constantly circulating: pond pump tubed water through to dribblers over all of my temperate CPs and drained back into the reservoir. It's essentially the same setup as you have there, only expanded. It worked great so I decided to try my hand at a Darlingtonia in the end of June. The tray sits in full sun and at first I was paranoid about high temperatures as I'd also read about the 81F = death "rule." Much to my surprise, even though the water temperature hit 85F for a few days during a hot spell, my Darlingtonia just kept on going. It sat in its original 4" pot of live sphagnum with a smidge of perlite. I know I was taking some big risks keeping it in such a small pot, but now I know Darlingtonia are tougher than I thought. Nothing ventured, nothing gained, right?

In any case, I'm still going to increase my chances at success by getting it into a 15" terracotta pot of equal parts dried LFS, turface, and peat, with a generous layer of live sphagnum on top. I'm placing the whole pot in one of the 3 new trays I'm setting up as part of another circulating system.

It looks to me like you've taken some really good measures to keep your Darlingtonia alive. One thing I would consider is throwing together at least a basic pre-filter for that pump of yours. Don't want all kinds of gunk gumming up the impeller in your pump, or clogging your tubing. I've kludged together pre-filters for both of my pond pumps and I have DIY pre-filters on the drains in the trays as well. Best of luck, keep us updated with photos, for better or worse!

As always, what works for me might not work for you, YMMV, and all that disclaimer jazz. Besides the fact that I'm also a beginner and am just sharing my own experiences. I hope it helps!
  • #13
Thanks for the replies everyone, there's a lot of good information on here. It seems like the the coastal varieties are really the only ones that need fussing over, and the mountain types are a bit hardier. What really surprised me was in the video x916krew posted, in which Darlingtonia were seen growing in hard, alkaline water. This information should be more readily available on the net! Every website I visited emphasized the cold roots above everything else. Admittedly, I do find myself worrying about my plant since it hasn't changed in appearance at all since I got it a few weeks ago, but I guess they are pretty slow growers. At least it hasn't died. I guess I'll have to wait until we actually get some hot days (100°F/38°C plus) to see how it does... It's been a strangely cool summer this year.

While some think my setup is unnecessary (and that may be true), it's definitely a relief not to have to worry about watering the plant every day, since I take frequent trips and often forget to do it anyway. The pump does keep the roots cooler and more aerated than if I had done nothing, so that undoubtedly can't hurt either. The pump has a little perforated cover over its intake, so it's doesn't suck in anything but the smallest particles, which don't seem to clog it.
  • #14
There are also numerous published descriptions and photographs of the coastal populations of Darlingtonia growing on seeps, banks and sloped bogs with water flow. As I recall Max's photos from a couple years ago has a photo of Darlingtonia growing on the seeps of a roadside embankment.

The pump does keep the roots cooler and more aerated than if I had done nothing, so that undoubtedly can't hurt either.

That's the bottom line: it doesn't hurt and experienced growers like Steve (Bugweed) Millar find a definite benefit using a circulating system vs daily top watering and the tray method.

See also Barry Rice's recent videos on Darlingtonia
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  • #15
Here is how I grow my Darlingtonia in Portland, Oregon. They are in a 7' by 3' bog with hardly no attention at all.



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  • #16
I just grow mine in a window in Portland, Oregon.
  • #17
Thanks again, guys. Those videos are cool stuff... I've been thinking of trying to find some Darlingtonia in the wild at some point in the future, and those videos help me get an idea of the habitat. Rob, it looks like you have a drip system going in your garden? Pretty cool!

Oh I've been wondering about one more thing... I keep reading that Darlingtonias are frequently found in areas with toxic serpentine soil. I happen to live very close to an area filled with serpentine rock - would it be beneficial to add a bit to my Darlingtonia's pot? Or do they just grow in those areas because little else does?
  • #18
It seems like the the coastal varieties are really the only ones that need fussing over, and the mountain types are a bit hardier.

The clone that I have is a coastal variety. I got it from Peter D'Amato, who told me that coastal varieties were hardier than mountainous ones. Although, like you, I seem to keep seeing over and over again that the mountainous varieties are hardier. If only I had one of each to set side by side ???
  • #19
Wow, that's kinda strange. Although, I guess the coastal form might be hardier if you're trying to grow it right along the coast in the Bay Area, with all the fog, low temperatures, and humidity all the time. Your area can get pretty hot in the summer though, so I guess it depends more on the individual plant and whether or not it came from good stock than the variety. I wanted to grow mine in full sun so it could get nice red pitchers, which is why I wanted to get the Sierra form.
  • #20
As long as the root temperatures stay below 81°F these plants will survive air temperatures in the triple digits. A nightly temperature drop helps too. Some of the "coastal" areas can get up to triple digit temperatures in summer. The mountain populations can tolerate larger daily temperature drops - high 90s/low 100s to low 60s/mid 50sF.

Coastal populations can have plenty of red coloring too.