Question
QUESTION: I am a hobbyist and enjoy propagating plants especially using stem cuttings.  I have learned a little bit about how to propagate stem cuttings from many articles on the Internet.  I still have a few questions though.  

1. I spoke with a woman who owns a plant nursery.  I asked her about propagating plants through stem cuttings.  Her advice seemed to contradict everything I抳e learned about propagating.  She said that I don抰 need to use a greenhouse or any type of covering to grow my stem cuttings nor do I need to keep heat on them such as a grow light or heat pad.  During cold months, I will be keeping my stem cuttings inside my home.  I have a few of my plants in pots in plastic zip lock bags.  They are in my laundry room sitting on top of my dryer where it provides good heat.  I also have a high voltage bulb on them.  I also have several plants on a table with no covering and no heat pads in my spare bedroom next to a large window.  What is the best way to ensure my stem cuttings grow roots?  Should I cover them or not?  Should I put them on my windowsill for lighting?  How often should I water or mist them?  What do you suggest I do to propagate plants using stem cuttings with the pots placed inside my home?  I also have a large shed outside.  Any advise using it for placing my pots?  Any advice will be GREATLY appreciated.

2. Is it that big of a deal if the leaves of the stem cuttings are touching each other in the pots?  Is it that big of a deal if the leaves touch the cover of the dome cover (or plastic bag)?

3. At Lowes they have a wire bookshelf with five shelves surrounded with plastic that they call a mini greenhouse that costs about $35.00.  If I bought this mini greenhouse, where in my house do you suggest I place it?  Or, would you suggest using one of those seed starting kits that have several places you could insert the stem cuttings along with a high dome to cover it?  If you like this better, where should I place it in my home?

4. Everyone online seems to suggest greenhouses or cold frames for propagating.  These are for outside aren抰 they?  I want to keep my plants inside my house; consequently, do I really need a greenhouse or cold frame?

THANKS A LOT

Frank



ANSWER: Hi Frank,
Thanx for your questions.

Growing techniques are just like people, they are different from person-to-person.  What may work for one does not necessarily work for another, etc.  There are some established procedures that most people use successfully and then there are other methods employed by others that work satisfactorily for themm.  I have grown cuttings without a greenhouse or bottom heat.  These things DO enhance success but are not required.  I have grown stem cuttings indoors and outdoors.  Some stem cuttings can be left in the ground for the winter and then will have roots by spring.  Using the top of a refrigerator or dryer is a good way to employ the excess heat created so you can provide this heat to your cuttings.  Ziploc bags can be used to root cuttings.  Unless you're using the high voltage bulb for heat, I would just use 40-watt shop lights for light.  I don't really see the need for the high voltage bulb if you have sufficient heat indoors.  The bottom heat really does enhance rooting success and I would recommend employing a heating pad at least part of the day (say at night..)Covering the cuttings helps retain moisture and humidity.  The big boys and girls use misting equipment where the cuttings are misted at regular intervals throughout the day to keep the cuttings from drying out.  If the cutting dries out, it won't produce a new plant.  

Basically, it has been my experience that using bottom heat, 40-watt shoplights, covering the propating environment with clear plastic or some kind of clear lid (to maintain humidity), rooting hormone and misting the cuttings a couple times a day, enhances success.  For your potted cuttings indoors, again, bottom heat of some kind, clear covering to retain moisture and to allow light, rooting hormone will enhance rooting indoors.  The outdoor shed can be used to transition plants that have already rooted and are not quite ready to go in the ground.  The shed can also be used for overwintering hardwood cuttings.  I

You should strip off all but the last couple of leaves of a stem cutting.  The leaves should preferably not touch each other or the sides of the propagator to prevent spreading disease.

I have used the mini-greenhouses outdoors when starting new plants.  You could place it in your spare bedroom to keep it out of the way but available for you to work with.  Personally, I prefer using 10X20 seed flats with warm, wet sand.  I put the rooting hormone on the cutting and just stick them into the sand and cover with the plastic dome.  Keep them on a special shelving unit my brother and I made (your mini-greenhouses will work...).  The shelving unit is right above a heater register (the vent from the heater in the basement) so there is periodic warm air coming up and no need for a heating pad.  I just make sure I maintain moisture levels.  To be honest with you , I'm not very good at remembering to consistently mist the cuttings.  

No, you don't need a greenhouse or coldframe.  They can be helpful if you're growing a lot of different cuttings.  Greenhouses and coldframes are wonderful for starting large lots of seedlings too.  You can grow cuttings indoors with a small shelving unit, 10X20 seed flats and domes, rooting hormone, 40-watt shop lights and heating pads.  I hope this helps.
Tom




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


Greenhouse   QUESTION: Thank you Tom for taking all of your time to answer my questions.  I have a few follow up questions:

You said in your response "The bottom heat really does enhance rooting success and I would recommend employing a heating pad at least part of the day (say at night..)"  Are you talking about a heating pad that everyone has for aching backs, necks, etc. or are you referring to plant heating pads?

I bought the four shelf small greenhouse from Lowes that I previously spoke about.  I attached a copy of it to this email.  I took three pictures of it and had them lined up side-by-side in one picture.  I put the greenhouse in my walk-in closet.  In the picture I have two grow-lights perpendicular on the wall behind the greenhouse.  I intend on buying a couple more grown-lights and then nail them on the wall horizontally so each shelf will have a light.  In the picture, I don抰 have the front of the greenhouse zipped closed.  It does zip close completely.  I put a thick plastic board on the bottom shelf to make it more completely sealed than it would have been had I not put it on the shelf.  If you owned this, what would you do to ensure that each cutting grows roots as hoped?  I think if I bought a bunch of heat pads for the shelves, I抎 go broke ha-ha.  My thoughts are to keep as close to 100% humidity as possible, I抣l spray mist on them daily and keep the lights on about 18 hours per day.  What do you suggest?

Thanks again for all of your advice!!!

Frank


ANSWER: Hi Frank,
Thanx for the followup.  Your greenhouse in the walk-in closet looks great!

I do not recommend using a heating pad that one uses for aches and pains as they may not be UL listed for contact with moisture which could cause an electric shock.  Check out this URL below for ideas about waterproof heating mats for horticultural purposes.  This is just an idea and not an endorsement of the company by me because I have no experience with them.
http://homeharvest.com/propagationaids.htm
You can also do a Google search for heating mats/pads to compare prices and quality.  This may help guide you to find something locally.

The lighting isn't as imporatant as the heat and moisture levels.  Concentrate on providing a warm environment and plenty of moisture.  If you can't afford heating pads and I do understand that, buy one when you can afford it until you have the desire amount.  Some of the cuttings will root whether you have bottom heat or not, the bottom heat is definitely an enhancement to success because the auxinx (plant hormones) are stimulated into action by heat better than just sitting in the ambient (surrounding) temperature).  The other thing you can do to enhance heat is to make sure that room is warmer than other rooms in the house.  Put a space heater near the greenhouse but bear in mind that space heaters need to be handled carefully so they don't cause fires.  I would get one of the space heaters that turns off if tipped over.  Also a space heater that doesn't have exposed heating elements.  There are many inexpensive varieties available at the discount stores.  I have a small one in my bathroom I turn on in the dead of winter so I don't freeze to death after I get out of the shower.  I think it cost $10 or $12.  Don't put the space heater inside the closet as this would definitely be a fire hazard.  Also, make sure the electrical cord from the space heater isn't in a position on the floor that could cause someone to trip.  I know some of this sounds elementary and I hope you are not offended by the simplicity.  I know how excited people get about starting a new project and I just want to make sure I'm covering safety aspects too.  I wouldn't want anyone harmed or their property harmed because I gave incomplete advice.  If you are able to suspend a 40-watt shoplight over the greenhouse safely inside the walkin closet, that's what I would do.

Once your cuttings start growing new leaves, you will have cuttings on various shelves that may not be getting as much light as the top shelf.  AT this time, it will be important to take those cuttings and place them directly underneath a 40-watt shop light.  Use a shelving unit that will allow you the suspend a 40-watt shop light (48" or 1.22 meters) above each shelf and place your pots underneath.  Once the cuttings have green leaves, it will be very important for them to get brighter light in order to grow healthily.  I would just run the lights 12 hours a day and mist them periodically.  It sounds like you have a great project.  Let me know how it goes.
Tom

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

QUESTION: Tom, I'm sorry for bugging you again.   

I put an outside spotlight in the greenhouse to help keep it warm inside.  I wonder though if this might cause the plants and/or soil to dry out.  Which is better, with or without the spotlight inside the greenhouse?  Would the spotlight suffice instead of your space heater suggestion?  

Would you suggest I buy two other grow lights to put them horizontally on each shelf of the greenhouse?

Is it that big of a deal if the leaves of the stem cuttings are touching each other in the pots?  Is it that big of a deal if the leaves touch the cover of the dome cover (or plastic bag)?

It was my birthday yesterday.  A friend bought me one of those seed starter kits that has 72 holes to plant seeds, a dome, and a heat pad.  Would you suggest buying a grow light for this kit?  Would you suggest that I put the heat pad in my green house or in the seed starter kit or would you suggest that I put the heat pad under some pots for a day and then move the heat pad to other pots for a day and on and on and on?

I recently bought a kumquat tree from a nursery.  I propagated some of the new growth and put them in a pot.  I used (as I always do) a rooting hormone.  If the leaves fall off do you think that indicates that the stem cutting is dead or what?

Thanks a lot Tom for your help and suggestions!!!

Frank

Answer
Hi Frank,
Thanx for your questions.  We're here to serve so ask as many questions as you like.

Whenever putting a light for heat or using the spaceheater keep safety in mind first.  Don't do anything that might have a potential for causing a fire.  That's why the plant heating pad is the safest although it's more expensive.  If you're using an outside spotlight, make sure the spotlight won't cause a fire.  The primary thing you're concerned with for now is heat.  The cuttings won't have a high light requirement until they start growing new green growth.  A spotlight that generates heat will have a similar effect as a space heater just please keep safety in mind.  I wouldn't want you to burn your home down or cause harm to you, your family or your property.

Eventually you will need lights on all the shelves that have growing cuttings.  To me, grow lights are a waste of money.  I have been successfully growing things under 40-watt shoplights that I buy at Walmart for $10 to $15 each.  The shoplights are 48inches long and replacement flourescent tubes are inexpensive.  Many people swear by using one warm bulb and one cold bulb for a fuller spectrum of light.  I use only cold bulbs and have had nothing but good results.

Yes, sometimes it can be a big deal if the leaves of the stem cuttings touch each other in the pots or touch the cover of the dome cover (or plastic bag). Disease can be harbored in these places and spread from plant to plant by this type of contact.  Cuttings are very susceptible to disease at this stage just as a human being is after having had extensive surgery.  The body's/plant's defenses have been compromised by trauma and the plant/body concentrates on healing and growing at the same time.

Happy birthday!  You don't necessarily need a growlight for you new seedstarter.  Just place it underneath a shoplight as I suggested above.  I would use the heating pad for whatever would give me the greatest results.  If you are using heat, it must be consistent because the cuttings will acclimate themselves to it.  A sudden withdrawal of the heat could have fatal effects.  It's better not to have any heat than to turn it on and off.  

The leaves that fell off your kumquat cuttings could just be the result of shock.  Give the cuttings about 8 weeks unless it is obvious that they have dried out and died.

I hope this helps.
Tom