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Carnivorous Plants/harbor freight greenhouse 6x8


QUESTION: Hey guys!! I will be as specific as I could so you can understand this question. I recently purchased a Harbor Freight 6x8 greenhouse and was wondering the best way I can keep the humidity in it. I grow a N. Miranda, Ventricosa, Lady luck, Drosera Capensis, Flytraps and sarracenias, and am waiting for my N. Sanguinia. I live in northeastern Pennsylvania and also want to know how to keep the greenhouse the right temp in the winter. You can check out my plants on youtube at tommys carnivorous plants. Thanks!!!!

ANSWER: Hi Tommy,

Wanted to tell you right off, that I did watch your videos, so I have some feedback on how you're growing your plants to help you improve what you're doing.  You must have put lots of work into those videos!

To answer your first question, with greenhouses, don't worry about humidity.  When you start getting plants in there, watering etc... the humidity tends to be high all by itself, and humidity is not where you want to put your efforts in cp care.  The most important growing factors are:

1.  Correct lighting and/or light intensity.  Almost all carnivorous plants are very high light plants.  Not providing adequate light is the #1 cause of plant losses for new growers, especially Venus Flytraps.

2.  Correct Water.  With just a few exceptions carnivorous plants need low-mineral water.  This usually means rainwater, melted snow, distilled water, or water purified by reverse osmosis.  One type of filter takes out minerals too, but only one, and it's ZeroWater.  How you water makes a difference with many plants.

3.  Correct Soil.  All carnivores are used to low mineral soil with very few nutrients in it.  (That's why they catch bugs!)  The soil is usually going to be peat moss or long-fiber sphagnum moss.  Often inert rock-like ingredients (perlite, sand, pumice, etc...) is added to these to create better drainage.  All regular potting soils have too many nutrients and will kill carnivorous plants.

These three things are the most vital to being successful growing cp.  Everything else is just fine tuning.  Things like humidity, misting, feeding, are very secondary to those three things listed above.  If to much attention is given to say, humidity, but a plant isn't getting adequate light, it makes no difference.  It's kind of like with us when we hear that vitamins are good for us, but we eat nothing but potato chips and cookies, it's not going to matter how many vitamin pills we take.  You're still not going to be healthy.  

I mention humidity since I saw that you were going to lots of effort to keep the humidity higher.  You were also misting.  Neither of those two things matter as much as adequate light, correct watering, and location to get the adequate light.

With your greenhouse, based on where you live, I strongly recommend you use it only as a cold frame.  I would discourage you from putting your tropical plants in there like your Nepenthes.  You can use a simple space heater to heat a little greenhouse like that, but since PA gets very cold in the winter, you would only be keeping the temperature inside in the upper 20's and 30's during very cold weather.  This would allow your perennial plants like Sarracenia and Flytraps to be dormant, but not have to be buried under mulch like they would need to be outside.  They will also appreciate the strong sun in there, but be sure to adequately ventilate it when it starts getting warmer.  Temperatures can rise to dangerous levels very fast in a greenhouse closed up.  You also don't want the perennial plants indoors during the winter since it's too warm and they wont' get adequate dormancy.  This is a very common reason for people loosing Venus Flytraps.

So Tommy, what kind of light do you have now over your plants on your plant shelf I saw on the video?  If you don't have a light, you need to consider getting one, or move your plants to directly in front of the window.  They look like they're not getting nearly enough light.  Unless your Drosera capensis is the "alba" variety, the tentacles should be red.  Also, your Nepenthes that are not producing pitchers, lack of light is the #1 reason for that.  N. x miranda should have a slightly reddish color to their leaves when they are getting adequate light.  A light will also allow you to keep the tropical plants in your room as opposed to putting them in the greenhouse which will be much riskier, and very expensive in heating in the winter.

I was going to mention too that whenever you get cp soil that is dry always thoroughly mix it with water before you use it to plant your plants.  Peat moss takes awhile to hydrate.  I like to put it in a bowl or bucket and knead it like bread dough to get it to absorb water.  Since you potted up a Sarracenia leucophylla rhizome that was still dormant, it will tolerate the dry soil until the peat soaks up the water, but some other types of plants, like sundews, would not.

I'm going to leave you with a very big recommendation.  Before you even consider buying another plant, consider purchasing our DVD's.  I'm not telling you this just to sell videos.  We produced these in our nursery to be a hands-on guide for the beginning carnivorous plant grower.  We don't just tell you what to do we show you.  For instance, in volume # 1 we show you how to mix soil, and pot up rhizomes.  In volume #2 we show you types of artificial light, and about windowsill growing for sundews.  Volume #3 goes into great detail on growing Nepenthes and other tropical carnivorous pitcher plants.  The money you spend on this education will save you many times over in not loosing plants to basic mistakes.  From watching your videos, I can see you're on the right track in many respects, but your going to have to make some major adjustments to keep from loosing some of them.

Once you're armed with that knowledge, feel free to join us back here on Allexperts if you have specific questions.  Our caresheet pages will help you lots in the meantime.

Good Growing!

Jeff Dallas
Sarracenia Northwest

---------- FOLLOW-UP ----------

QUESTION: I have a 60 watt heat lamp. and my drosera is an alba.Also what if I used 2 space heaters and bubble wrapped the greenhouse in the winter. Would that work? Also im 13 so I don't make much money. Would you consider me getting a mister or fogger for the greenhouse? Also what type of grow lights work the best for greenhouses. Can you give me the brand of lights that you recommend the cheapest but the best? I really want to grow my nepenthes in the greenhouse. Can you give me some tips on that.Your response to my last question was really helpful. Thanks!!!

    Hi Tommy,

One of the very first things I said in my previous post was don't worry about humidity.  A humidifier or fogger in a greenhouse is a total waste of money.  It will be more than humid enough.  The humidity requirements of carnivorous plants is something that is totally overblown both on the internet and in many books.  It's a secondary consideration at best.  Besides, you live somewhere that is a humid climate already.  People who live in places like Arizona it does matter more, but not on the East Coast.

One standard 1500 watt space heater in your 6 x 8" green would probably keep it quite warm.  That's a pretty small area.  Here's the problem with you using it for very temperature sensitive tropicals.  In the winter let's suppose you have a power outage in the middle of the night during some very cold weather.  Unless you have a power outage alarm or could get up to start a gas heater in your greenhouse, or have a generator going, your tropical plants are dead.  This is also assuming that you're not gone on a holiday or vacation too.  If you're using the greenhouse as a cold-frame for the winter hardy species like Flytraps, Sarracenia and North American Sundews, they could take the cold for awhile.  Our climate here in Oregon is nowhere near as cold as Pennsylvania, and we have both gas and generator back-up, and even with that, we've had some close calls.  Setting up a light shelf in your room is so much easier, and cheaper.  It will cost you way more money to keep them in the greenhouse.

The simplest, most cost effective plant light is a simple two-tube shoplight with cool-white tubes.  You can use either T12 or T8 tubes.  Cool-whites work very well, Daylight type natural spectrum tubes are good too, but cost more, and are not quite as bright.  We have a chapter on our volume #2 DVD all about this.  I've used this kind for years:  You would also need a simple plug-in type timer.  You can hang this above your plants and adjust the height with the chains that come with them.

Tommy, here's a few important things.  All of the things I'm telling you are based on 35+ years of experience growing carnivorous plants.  I've been where you are, because I started trying to grow cp a couple years before you (age 10).  The things I'm recommending are to help you be successful and not kill as many plants as I did.  It's really tempting in this day in age to think "Oh, I can get all the info I need on the internet."  There's some good information on the web, and some very bad information, and a whole lot that will won't make sense until you have more experience.  I really, really, really recommend that the next $$$ you spend is on information.  The Savage Garden, by Peter D'Amato is the best book out there.  I've mentioned our DVD's.  They will really help!

Good Growing!

Jeff Dallas
Sarracenia Northwest

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If your carnivorous plant is showing poor growth, discoloration, abnormal leaves or possible infestation, the expert growers at Sarracenia Northwest can help! They have a great depth of experience dealing with diseases, pathogens, and abnormal growth in carnivorous plants.

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