Do Darlingtonia need cool roots?

[kulamauiman]

By the looks of it you need bigger pots, why not try planting them direct into trays?

Given time I suspect they will just spill out of pots and take over

[Wire Man]

This gives me a little hope for my seedlings surviving VA summers.

[Alexis]

Ah, the cobra cold roots myth! It amazes me that people mess about with ice cubes and water pumps.

My cobras live in full sun and are kept in conditions no different from sarracenia. They are in big black pots and some are in peat/perlite and some are in live sphagnum. They sit in about 5cm of water. Summer temperatures in the greenhouse reach 100F.

I've repotted them in the middle of summer before and the sphagnum has been so hot, steam was rising from it. They're as tough as old boots.

The only plant that gets too hot in my experience are cold-temperate butterworts. Even sarracenia purpurea ssp. purpurea can take it hot.

I think the more plants you have, the less you mollycoddle them as individuals and the happier they are when left to their own devices.

[RL7836]

As it is a half tray it has wider fluctuations in temperature than the larger trays. The maximum root temperature I recorded was 32.4C - 90F.

What are the normal nighttime lows?

[fredg]

Ah, the cobra cold roots myth!

[mato]

So, everyone who thinks this is a myth, do you all have location data for your plants? I will tell you flat out I've seen the difference between the mountain and coastal varieties, as far as heat tolerance is concerned.

[fredg]

So, everyone who thinks this is a myth, do you all have location data for your plants? I will tell you flat out I've seen the difference between the mountain and coastal varieties, as far as heat tolerance is concerned.

Is your data available?

[RL7836]

I applaud Fred for diligently collecting temperature data over the course of the summer. This type of information certainly helps to get us closer to understanding the needs & limits of Darlingtonia.

Ah, the cobra cold roots myth! It amazes me that people mess about with ice cubes and water pumps.

My cobras live in full sun and are kept in conditions no different from sarracenia. They are in big black pots and some are in peat/perlite and some are in live sphagnum. They sit in about 5cm of water. Summer temperatures in the greenhouse reach 100F.

I've had many permutations of this discussion with people. What I've found quite consistent with these discussions is that the people who assert that cobras do not need cool temperatures - come from places where cool temperatures are the norm - especially cool nighttime temps. Just once, I'd love to see the originator of a thread like this come from a non-mountainous, mid-atlantic state (or any of the gulf-coast states). Even outside these horribly Darlingtonia-unfriendly areas, success with cobras is rare in most of the southern & eastern USA. Frankly, I'm a bit surprised at this. If it is not the temperatures - are there any other potentially-viable theories why no one has success here? I suspect that there would have been at least a handful of reasonably competent growers within the legions of those who've tried & failed ....