Can one tell if it's time for dormancy?

[jonnyq]

Greetings, all,

Quick dormancy question from a novice...

I've read that a good sign of dormancy is the yellowing/browning of leaves, slowing of trap response, slower leaf/trap growth and growth of the ground-hugging winter leaves, with the broader petioles.

I've got a plant that's growing in a climate-controlled office. (Actually, she's got about 11-13 leaves, which means that she's split into 2, no?)



The temperature fluctuates between 70F and 80F daily, but rarely below, and never above. I'm using a CFT daylight spiral bulb (~10W if memory serves) at a desklamp on a timer. I started it out at 14 hrs/day (on at 2AM, off at 4PM), but have slowly been reducing the # of hours as the winter approaches to try to approximate the seasonal light change. (Unfortunately, there's nothing I can do about the average temperature.)

I've read that there's little I can do to "trigger" dormancy, and that the plant will enter it whenever its cycle dictates... and that trying to "force" dormancy by doing the prescribed [plant + rinsed roots + damp sphagnum + dampish paper towel + ziploc + refrigerator] could kill it if it's not ready, yes?

Well, it's almost November... Growth of new leaves has indeed slowed, though none of the newest seem to have the wide petioles of the older leaves... Other than that, most of the leaves seem healthy and green; only one or two of the older leaves have yellowing, and that's mostly at the margins of the petioles.

Has anybody found that steady year-round warm temperatures "confuse" the dormancy cycle?

Is my plant acting normally, i.e. "on schedule" and I'm just being paranoid?

Any recommendations of how/when I should proceed?

(Thanks again, everyone, for all of the fantastic information here!)

[zhilin]

I think in your office, it never goes into dormancy. Dormancy is mainly triggered by temp below 50F with greatly reduced light duration. A obvious sign of dormancy is brown and black leaves.

[GregNY]

welcome fellow long islander. bellmore area here. I am new to the whole scene of CP growing, but I can tell you what I know. I've been growing some sarrs and vfts outside since the beginning of spring. from what I hear, outside is the best for them, if kept well watered, and they should enter dormancy naturally due to the gradual decrease in weather over the latter months of the year. sounds to me like your plant is approaching that stage eventhough you've noticed no different in leaf coloration.

from what i've read, not allowing your plants to go into dormancy wont necessarily kill the plant but the following year you may notice "off" or sluggish growth, and although I've read you can grow like this for a year or 2, the plant will gradually continue to diminish in quality until it finally dies off.

hope that helped a bit in deciding what you should do. personally, i'd either stick them outside from now to heavy frost to induce that dormancy that they seem to be getting ready for and then, when frost comes, either take your chances outside through winter with the plant or sticking it in a cold, dark area like a cold basement/garage. just some thoughts for you....good luck

[tippitytwitchit]

Hi Jonny. Sticking the plant in the fridge won't kill it. Instead, that is the best way to trigger dormancy. Just don't leave it in the office fridge, someone is likely to toss it, or eat it! Put it out on your porch for a few frosts, as Gregny suggests, then put it in the fridge 'till apporoximately Valentines Day.

[Aidan]

Oct 30, 2009 22:32:45 GMT tippitytwitchit said:

...that is the best way to trigger dormancy.

More suspended animation than dormancy. As noted above, the plant requires the cues of reduced day length and temperature. Slamming a fridge door on a plant gives it no time to adjust and fridging plants ought be the last resort of the desperate.

[sarracenialover]

Jonnyq, you should really grow your plants outdoors where it will will grow with the seasons. indoor growing reauires more work to maintain the plants i.e. watching for fungus, helping the plants go dormant instead of just leaving it outside and watering it when its tray goes dry.
Venus's Flytraps REQUIRE dormancy to grow long term, they need the rest in winter.

[kitkor]

Oct 31, 2009 18:17:35 GMT @sarracenialover said:

Venus's Flytraps REQUIRE dormancy to grow long term, they need the rest in winter.

I'm not so sure that's entirely accurate. I worked with Dr. Stephen Williams for a bit and at that time he had been growing the same VFTs in the college greenhouse for nearly 20 years. As far as I know, temperatures never dropped significantly. These plants were robust all winter and showed no real signs of dormancy. The number of inflorescences I had to cut down every spring suggested these plants were not suffering for their lack of dormancy.

[mmlr38]

Nov 1, 2009 23:25:09 GMT kitkor said:

I worked with Dr. Stephen Williams for a bit and at that time he had been growing the same VFTs in the college greenhouse for nearly 20 years. As far as I know, temperatures never dropped significantly.

Were they under lights or did they receive natural sunlight? If they received natural sunlight, then that may have been enough to signal them to enter dormancy even without the dramatically reduced temperatures.

Also, the "As far as I know" clause in your above statement is somewhat of a disclaimer. I'd like to know what the average temperature was in the greenhouse in the winter.

And I've read before that Dionaea may be able to divide rapidly enough (if they're healthy) that they can avoid going dormant by generating new plants as the introduced plants on the island of Jamaica have done.

In any case, I've never seen any verifiable documentation of a Venus fly trap growing continuously under fluorescent lights on a fixed photo period for more than one season without a dormancy.

If the original poster wants to ensure that the plant survives, I'd recommend taking it home and giving it a proper dormancy.

Oh, and just because a plant has 11-13 leaves doesn't necessarily mean that it's divided. I've seen plants with over 20 traps that were a single rhizome grown by Steve Doonan.

[kitkor]

Nov 2, 2009 0:24:46 GMT mmlr38 said:

Were they under lights or did they receive natural sunlight? If they received natural sunlight, then that may have been enough to signal them to enter dormancy even without the dramatically reduced temperatures.

Also, the "As far as I know" clause in your above statement is somewhat of a disclaimer. I'd like to know what the average temperature was in the greenhouse in the winter.

Mostly natural sunlight augmented with overhead lighting (don't recall what kind of bulbs) when it got dark. Average temperature in there had to be in the mid-60s to 70s or the tropicals would have suffered. It was also comfortable to walk through any time of day or night throughout the winter. We had a min-max thermometer and I remember writing down the temperatures for data collection, but I don't have those notes anymore. "As far as I know" referred to the estimation on average temperature over the 20 or so years he's had them in those conditions. The building and greenhouse were built in the 80s, which is around the time he began teaching there. He could have had the plants under different conditions and altered them by the time I was his student.

Regardless, I think dormancy is not necessary the first year you buy a plant from a home improvement store. If the plant hasn't been getting the cues for dormancy, sending it abruptly into dormancy could harm it. I'd wait a year and do it next winter.

[tonge50]

Nature knows best.
The weather is getting cooler and the days are shorter. The mature taps are dying back, but there is strong center growth. The new growth is developing slower than it did in the summer. They just seem to be winding down after their first season here. I had expressed in another thread that I was going to put them in the garage to stay cold and to keep them out of the light. Another member suggested that I let them have some sun during the winter and they will continue to develope slowly until the weather warms up and the days start to get longer again. That sounds like good advice to me. Just let the daylight and temperature guide your plants through the winter. ;D
Nice looking flytrap jonnyq.

[zhilin]

Nov 7, 2009 8:58:42 GMT tonge50 said:

Another member suggested that I let them have some sun during the winter and they will continue to develope slowly until the weather warms up and the days start to get longer again.

Hi, tonge50,

In this case (let it continue to grow slowly), does this mean that the plant doesn't enter the dormancy?

[tonge50]

I'm just guessing. I am new to growing CPs of any kind. Unless it gets really cold here in the SF Bay area, I don't think the crown will die back entirely. My traps have slowed down, and as the pictures show, the long petiols of summer are dying back on all the plants.



New traps continue to appear, but they are developing much more slowly than during the long, warm days of summer.



I expect that they will seem to stop developing all together for a while until the weather warms up and the days get longer. I'm going to try letting my fly traps figure it out for themselves naturally.

[Aidan]

Growth slows dramatically as plants enter dormancy, but does not usually stop entirely. The majority of summer/fall growth will die back, but not usually all. But, plants and conditions vary and some may die-back completely to the rhizome.

[jonnyq]

I just wanted to thank everyone for their great advice and observations...

In following the advice here, I did indeed move my flytrap outdoors... I began by acclimating the plant to non-office temperatures by moving it and the daylight-bulb lamp to a windowsill at my house.

After half a week of the lowered temperatures, I moved it outdoors to acclimate it to the natural daylight cycle. I am thrilled to say that it flourished far more than I would have anticipated for a CP growing in sunny Brooklyn.

On December 1st, I used the guide at www.world-of-carnivores.com/flytrap_fridge.html (more or less) to put my barerooted trap to fridge dormancy. (I hadn't realized that the plant was grown in pure long-fiber spaghnum. It was trickier to bare-root than I thought.)

In either case, I check on the plant once every three weeks or so. It seems to be doing well. Surprisingly, no sign of overt fungus, though there's a little browning around the edges of the leaf tips, which is to be expected. There are two new leaves that have begun to develop, but clearly they're developing extremely slowly, which is as expected.

So far, so good, and thank you to all of you for the insights and advice, and for the continued discussions and topics that I lurk around and read when I'm not doing my infrequent posting...




(And this is off-topic, but some of you might find amusing what I named my ship on Star Trek: Online. The rest of you might simply roll your eyes, but I hope that either way, this will taken as the homage it's meant to be.)



(I'm hoping to name the next ship USS Nepenthes.)

Thanks again!