Plant Propagation Taking Cuttings

by Doug
(His Island)

Here's an article and video on taking plant cuttings. Feel free to ask any questions you might have in the comment section. As always, I'll do my best to answer a few of them in a followup email to those registered for the course.

Here’s how to take a tender tip cutting.

Here are the conditions for success in successful plant cuttings.


What Soil to Use

I use one of two media for rooting my plants. The first is regular artificial soil (like Promix) It is sterile, weed free, well aerated and drains well so tender roots can easily grow.

I’ve also used florists foam for some cuttings and find it does particularly well at holding moisture for hard to root plants that do not like or require mist systems.

For average use, the artificial peat soil is cheaper and quite adequate. On the home scale, it’s almost all I use now.

Warmth

You need to keep the soil and plant warm. When I say warm I mean that soil should be around 70F. Remember the soil temperature will be approximately 10F lower than air temperatures. So an 80F air temperature is required to keep a 70F soil temperature.

Tender, easily rooted plants will root at lower soil temperatures but if you want to root woody plants like roses or if you want to get good success rates, you’ll have much better results with the right soil temperature.

Can you do it without this heat? Sure. There are tons of folks who stuck a cutting in a glass of water and the plant rooted. But there are far more who had it rot off.

If you don’t heat your plant cuttings, rooting will be uneven and you’ll get a lot of death in those cuttings.

Moisture

The first rule is to always use warm water (baby bottle temperatures) when watering your cuttings. You don’t want to throw a thermal shock at them.

The second is to never let them dry out. This means the soil should not dry out but equally importantly, you need to maintain a high humidity around the leaf so it doesn’t sweat out more water than it can absorb or contains (losing too much moisture is wilting - and plants won’t root if they wilt)

We do this in two ways.

We use an anti-desiccant. Spray this waxy-like substance (sometimes sold as Christmas tree preservative) onto the top and bottom of the leaf to clog up the leaf “sweat pores” (called stomata) This stops the cutting from losing any moisture.

Another system is to enclose the cutting. Lids that fit over top of propagation trays, pop bottle bottoms are cut off, glass jars are upside-downed over cuttings etc. There are as many techniques out there as there are gardeners but all do the same thing - they reduce the moisture loss around the leaf.



Softwood Plant Cuttings Themselves

When you talk about taking the softwood cuttings themselves, the objective is to take a cutting that is approximately 2-3 inches long. I have rooted one-half inch cuttings of rare plants and 5 inch cuttings of shrubs but the optimum length is two-three inches.

There is no way you can explain how to recognize the “feel” of a softwood cutting in order to know when it is “ripe” for rooting. Part of the problem is that different plants have different stages when they are ready for rooting. A rose will be ready when the thorns “pop” off when pushed sideways. Not when they bend or fight back.

A geranium will be ready when the stem is light green and actively growing. Neither the rose with too-green thorns or the geranium with woody bark are likely to root easily (although it has happened – this is not a precise science at the amateur level).

So - the “feel” is experience but generally - take the cutting when it gets 2-inches or so long and is green and tender.


Rooting Hormone
If you provide the right conditions, you don’t need it but I do know gardeners who swear by it.

Understand that, once opened, the shelf life of the rooting hormone is about 6 months. If you’ve been using older material and having success - congrats -you can toss it out and forget about using it because it’s not doing anything anyway. (you’ve just taken off the training wheels)

Woody plants might get a benefit from it but tender annuals and perennials do not require this assistance contrary to what the marketing folks will tell you.

The other note I’d leave you with is that if you get the rooting conditions right, you don’t need the crutch of rooting hormone. And rooting hormone will not replace providing proper rooting conditions.

How Long to Root the Cutting?
Here’s a rough guideline if all rooting conditions are perfect.

** 10 days to 2 weeks for tender annuals
**Several weeks for soft perennials.
**Longer for woody stemmed shrubs and roses.
**Months for stems with harder woody stems.

There are way too many conditions to give hard and fast answers to that question but those are general guidelines


Can You Tell Me How Long XX Plant Should Take?
I’d like to but…. (see above) it depends on too many variables.

Your best bet is to simply do it. Take that cutting, make notes on the labels (you do label the cuttings don’t you) about the date of cutting and then see how long it does take you.