A Hankering for Houseplants

Well folks, we've reached February. That means that spring, and the garden preparation that comes along with spring, is not that far away. While we're still hunkered down indoors though, I thought we could take a moment and circle back to our friends, the houseplants. Through the bleakest parts of winter, our houseplants bring us life, joy, and a reminder of what's ahead. For those of us without a garden or yard, our houseplants play that role all year-round. So, in honor of our houseplants and the special place they hold in our hearts, let's talk about a few of my favorites! 

Today, we're going to shine the spotlight on three plants with very unique foliage: the UFO plant (Pilea peperomioides), angel wing begonia (Begonia spp.), and triostar stromanthe (Stromanthe sanguinea). All three of these plants are fairly easy to grow (note: the triostar stromanthe is a bit more particular about moisture), but if you're a beginner and want to start with some truly beginner-proof houseplants, check out our latest houseplant post here. 

UFO Plant (Pilea peperomioides).

Native to China, the UFO plant (Pilea peperomioides) has become a popular houseplant in recent years, largely due to its ease in propagation. While many houseplants are propagated via cuttings (which require time and patience as you wait for your cuttings to take root), the UFO plant also self-propagates by producing offshoots, or babies, at the base of the plant. These rooted babies can be easily separated and shared with others, giving this plant its other common name, "the friendship plant".

The UFO plant gets its name from its circular leaves, which extend from stems that are centrally attached to the base of the leaves. This type of leaf is referred to as "peltate", and gives the appearance of the leaves floating in space (hence, UFO). The leaves of this plant prominently grow towards the light, so you'll want to rotate your plant to keep it growing symmetrically. (In case you're interested in the mechanism behind this well-known phenomenon: a plant growth hormone called "auxin" concentrates where there is less light exposure, stimulating the growth of cells on the side of the plant that receives less light. As a result, the side that receives less light elongates, while the side that receives more light doesn't; together, this causes the plant to bend towards the light.) 

Like many houseplants, this plant benefits from bright, indirect light; while it can adapt to less light, less light will likely result in a  more leggy plant. You'll want to pot the UFO plant in a well-draining medium, such as one largely made of coir, and water every 1-2 weeks. 

An angel wing begonia (Begonia sp.) cutting's first baby leaf!

The same angel wing begonia (Begonia sp.) from above, one year later.

There are many, many different kinds of begonias, but they can generally be separated into three groups based on the presence of underground storage organs. Of those three groups, the fibrous-rooted begonias contain some of the begonias we are most familiar with, such as wax begonias (often seen as annuals) and cane-like begonias (often seen as houseplants or annuals). Cane-like begonias, which are our focus for today, are also called angel wing begonias due to their wing-shaped leaves (as seen above). Cane-like begonias have jointed stems and, at every joint, you should find a leaf and/or a cluster of flowers, if in bloom. Some have polka dot-like spots on the foliage, which is why I find the leaves of this plant so unique and cool!

Due to the large variety of species and cultivars within the cane-like begonias, it can be difficult to identify a cane-like begonia down to the species/cultivar. You can see that I denoted my begonia as Begonia sp. for this very reason (sp. indicates that the species is unknown or doesn't need to be specified). Regardless of specific identification, cane-like begonias have similar needs to grow well. They generally do best in bright, indirect light, in a fertile soil, and they like to be watered as soon as the soil surface is dry to the touch. Cane-like begonias benefit from pruning or pinching in order to promote bushier growth.

Triostar stromanthe (Stromanthe sanguinea)

As its name implies, Stromanthe sanguinea (sanguinea means "blood red" in latin) features dramatic reddish-pink coloring, particularly underneath the leaves and at the base of its stems. The tops of the leaves hint at a pink color as well, although it is much more subtle as it blends into the white and green variegation. These glossy, colorful leaves make this plant an absolutely stunning houseplant, which is why I just had to buy it a few weeks ago. The triostar stromanthe, commonly also called "tricolor", has a mechanism by which it can position its leaves according to sun exposure, and also folds up its leaves at night, exposing the bright coloring underneath. 

Native to the rainforests of Brazil, triostar stromanthes prefer warmer temperatures and humidity. During the growing season, it's best to keep the growth medium (which should be soilless) consistently moist. In contrast, the medium should have some time to dry out in between waterings during the winter. While bright light is best to maintain its bold coloring, triostar stromanthes can do very well in lower light as well. Unlike other houseplants we have discussed, propagate these plants by dividing the clump. 

Do you have any tips for maintaining and propagating these houseplants? Let us know below!

References:

Guide to Begonias: https://edis.ifas.ufl.edu/publication/EP581

Cane-like Begonias: https://www.begonias.org/cane-like-begonias-like-bamboo-with-flowers/

Stromanthe sanguinea: https://hort.extension.wisc.edu/articles/stromanthe-sanguinea-tricolor/

The Simple Trials of Seed Germination

Posted by: John Stolzle, Jefferson County Extension

Despite the lingering winter weather, spring is on its way. And though it may yet be just a little too early for preparing flowerbeds, raised gardens and the like, now is a great time to test the germination potential of any seeds which you may have saved in seasons past.

Seeds from leftover packets or harvested from a previous year’s crops can remain viable for many years when stored under the right conditions (CSU Factsheet on storing seeds).

If you do not have any seeds from last year, you might consider saving some this season. Seed swaps and seed saving courses are becoming popular, and carrying over seeds between years can be a fun to way to maintain continuity between multiple growing seasons. For further reading on this topic, I might point you to 'this' seed saving blog post.

Generally, vegetable seed packs sold in Colorado are required to germinate above a mandated minimum percentile, although the relative longevity of these seeds can vary. Storage conditions (for example, temperature and humidity) can affect the viability of leftovers, or seeds gathered at the end of a previous season. A quick and simple test can help to assess how your seeds are doing.

I’ve been running some seed germination experiments and would like to share the process and some results.

Overall, the methods are simple: Place 10 (or more) seeds on a damp paper towel, roll/fold up the paper towel, and check it every few days. Some additional tips and tricks are presented below.

Step 1: Seed Selection

Discard any broken, crushed, or otherwise damaged seeds.

Step 2: Preparation
To help prevent contamination, clean off a countertop or other workspace as best you can, and wash your hands. A paper towel or two can act as buffer between the “germination paper towels” and a worktop. 

Lay out two connected paper towels and then wet them with water (I used distilled water). Next, place your seeds in rows on the bottom portion of the two paper towels (image B.) - this will aid in later counting. For the most part, the more seeds you use, the more robust your results will be. In the photos, I was testing ‘ancient’ seed packets and therefore used many seeds, but 10 or so should suffice for a quick assessment.

Following seed placement, horizontally Fold Down the upper portion of the two paper towels (Image C).

Tip. 2-ply paper towels were used in these tests, they held up fairly well.

Step 3: Seed Placement & Folding

In image D., below, I made a mistake which I think is worth highlighting – I placed seeds on both the top and bottom halves of the paper towel and just starting rolling it up. Because the paper towel was not first folded (as in image C.), seeds stuck to the outer layer of the paper towel when it was unrolled - This made later counting much, much more difficult as seeds were stuck to either side of the paper towel.

After Image C., The next step is to make roughly 1.5-inch folds/rolls in the paper towel until you have something like what is seen in image E. For organizational purposes, I combined multiple germination tests (for different plants) and placed a rubber band around them (image F.). To prevent drying out, your germination test(s) should be placed in a plastic bag of some sort.

Tip: The paper towels should be damp but not dripping wet.

Step 4: Results & Analysis

By day 3 some seeds in my tests had already begun to germinate; the number of germinated seeds should be counted and recorded. 

Tip: It may be necessary to periodically rewet the paper towels.

But, as it goes, a few problems were encountered....

Image K.: Some seeds became fuzzy with fungi; this can largely be prevented through additional aseptic steps (discussed below). 

Image L.: It can also be easy to convince oneself, as I did, that seeds are germinating when actually they are not. Coriander / cilantro seeds are tricky, in my opinion; when I stared at them long enough, I began to see that they had germinated! I snapped a photo and compared it with the same seeds a few days later, and also found some un-tested coriander seeds to compare against... no germination had actually occurred.

Image N.: Unfortunately, a major blunder occurred during my eagerness to cleanup. Days after starting the test, I realized that I had tossed out the seed packet for the corn cultivar which I was testing! I highly recommend holding on to those, as well as making good reference notes!

Tip & Note to Self: It can be very helpful to keep seed labels and few reference seeds around!

Step 5: Calculation

The final step is to calculate your results! After 7 – 10 days, divide the number of germinated seeds by the total number of seeds in your trial.

In my tests, the pepper seeds did not respond very well and demonstrated a 45% total germination rate. I believe that this was most likely due to issues regarding temperature.

Temperature & Germination Time:

Knowing the difference between Warm and Cool season crops, as well as the general number of days until seed germination, can be incredibly helpful – A wonderful cheat sheet can found in Table 1 (pg. 3) of the following CSU – Colorado Master GardenerGuide.

Peppers, for example, prefer a soil temperature of 80°F and are notorious for taking a long time to germinate (an expected 10-20 days). Watermelons have similar temperature requirements to peppers but are expected to germinate somewhere between 3-12 days.

Tip: A seed propagation or heating mat can greatly improve the germination rate of seeds.

Aseptic Technique:

Implementing additional aseptic or seed disinfesting techniques can reduce the likelihood of contaminated seeds (Image K, above); if contamination is a problem or concern, the following publication from LSU Extension & AgCenter may be of interest.

Replication:
Repeating a ‘trial’ or single germination test two additional times (with each test occurring on a different day) would add to the robustness of a test’s final results. This means re-doing the 7-10 day trial, three times independently and weighing your overall results... But everything is a balance. Some seeds should be saved for planting in the soil!

So What? The value of knowing seed viability

Knowing the germination potential of a seed cache allows one to plan accordingly. If seeds present a 0% germination rate it may be due to a faulty test, in which case it can useful to re-test the seeds or look into temperature requirements or other confounding factors. If the seeds present a 90% germination rate, AWESOME! - One can be fairly confident that planted seeds will germinate successfully; whereas with a 0% - 50% germination rate, it may be necessary to plant seeds more densely or to check over one's seed storage conditions.

Good Luck & Happy Gardening! 

Victor Frankenstein should have taken up gardening

Posted by Carol O'Meara, Boulder County Extension

Cue up some Edgar Winter, it’s time celebrate the birthday of one of our most iconic Halloween bad boys: Frankenstein.  Two hundred years ago, Mary Shelly published the story of the reanimated monster that’s shuffled and groaned its way into the pantheon of ghouls that define the season.

Shelley shocked the world with her gothic horror treatise, widely regarded as the first true science fiction novel rather than fantasy, because it drew on scientific concepts of the day.  Pulled together from pieces of cadavers, the monster was reanimated through electricity from lightning.

A sewn-together creation of bits and pieces is nice and all, but gardeners know her tale isn’t as far-fetched as we’re asked to believe.  We’ve been doing this for thousands of years.  We live with creatures grafted together all the time; in fact, we search them out and make them the centerpiece of our landscapes.

Some are subtle; so seamlessly grafted you don’t realize its two different plants put together.  Others show the graft proudly, and gardeners use this to guide them in planting to proper depth.  Grafting provides us with plants that are sturdier, more disease resistant, or smaller than the original.  It’s how we get cultivars of the same fruit on tree after tree in orchards so we can enjoy Honeycrisp apples or Cresthaven peaches. 

In order to make sweet, edible apples one needs to grow the exact cultivar by cloning as grafts on rootstocks. If you try to grow them from seed, you get the result of apple flowers crossing with other, usually crabapples.

It’s also how we have trees sporting several different fruits on the same plant.  Often called “fruit cocktail” or “fruit salad” trees, gardeners with big desires but small space can have it all: with four, five, even six different fruits on a single trunk.  Nectarines, plums, apricots, and peaches or red, green, and yellow apples come together in a fusion of flavor.

Scientists are running wild having successfully grafted fruit trees they’re grafting anything that doesn’t move in the garden: tomatoes, melons, the neighborhood rabbits.  Ok, maybe not the rabbits, but horticulturists are very excited about grafting.

Clones, too, surround us; they give us perfect replicas of plants we covet at other’s homes or businesses. Technically, the definition of plant cloning is human-controlled asexual propagation of a plant, which doesn’t sound fun at all. But we do it all the time.

While Victor Frankenstein raided graveyards for his body bits, we raid plants we see while walking the neighborhood or sitting at the doctor’s office awaiting our turn.  With a quick, surreptitious pinch, we snitch a bit of plant to put in water for rooting, thus cloning the plant.  Love that African violet?  Pinch off a leaf and plant it.  The begonia at an atrium in the mall?  They root nicely from leaves as well (readers: denuding a plant you don’t own is unethical.  Ask permission before taking anything from the plants you see).

When it comes to bringing things back from the dead, gardeners have much in common with Victor; anyone who’s had a jade plant fall and shatter into pieces knows the desire to resurrect it by shoving a bit of stem or leaf into potting mix (the leaves should be dried a bit before doing this, but that’s a different story).  It takes a while for the leaf to root but shocking it with electricity to speed things up would end in disaster.

Ultimately, Victor wasn’t such a bad guy; he simply needed to take up gardening. 

Exercise Your Green Thumb

Posted by:  Amy Lentz, Weld County Extension

Mother nature is really testing gardeners this winter by teasing us with this long stretch of summer-like weather, making it hard to resist the temptation of going out in the yard and planting something!  

One way to exercise your green thumb in the off season is by propagating house plants. Last month, Sherie Caffey wrote a fantastic blog titled Adventure in Propagation about this very subject!  So for this blog, I thought I would expand on this to show you a few additional species that are easy to propagate at home with no addition of rooting hormone or special conditions...just using a slightly different planting system.

When I moved to Colorado last summer, I decided that I would donate my houseplants to the university nearby rather than try to transport them across the country in a moving truck. I am glad that they are being put to good use to educate others, however, once here, I began to miss some of my old plants. So when I went back on a trip last fall, I just had to drop by the university's greenhouse and take a few cuttings to bring back to Colorado. I decided to choose the easiest species to propagate so that they would successfully make the journey back. 

Tropical Plant Collection at Morehead State University in Morehead, Kentucky.

 After taking the cuttings I put them in a simple plastic bag with a small amount of water, just like Sherie recommends in her blog. I left them in the bag for about a week with the top slightly open and making sure they didn't dry out.

My new collection includes the following easy-to-propagate houseplants:

Purple Wandering Jew (Zebrina pendula)

Golden Pothos (Epipremnum aureum)

Ghost Plant (Graptopetalum paraguayense)

Baby Rubber Plant (Peperomia obtusifolia). 

Jade Tree (Crassula argentea)

The Wandering Jew is a vigorous grower, so I decided to go straight into a larger container, knowing that in a few months the three cuttings will have filled that container and be ready for an even bigger one. They are super easy and will grow rapidly, so give these guys their own space.

After just a week in the plastic bag with water, the roots were already very visible!

I stripped off the bottom two sets of leaves and planted them into their new pot.

Everything else went into the same shallow terracotta dish, but any shallow container with drainage will do. Because these are easy to propagate species, you don’t have to worry about using a special propagation mix.

I spaced the various cuttings in the dish (including the pieces that had fallen off the succulent cuttings), planted them and watered them well. Using what I had on hand, I found a couple of plastic spoons to use as a support for my homemade humidity tent that was made from self-sealing plastic wrap. I placed the dish in indirect sunlight by placing them on my kitchen counter near the window. Do not put them in direct sunlight as it will bake the poor cuttings!

 

 

I kept the potting mix moist, watering every other day, and then came the hard part...waiting! After about 10 weeks, I checked the cuttings to make sure they had rooted by lightly pulling up on the plant to see if there was resistance…and there was!  

Look at those roots!

 

The Jade Plant decided that it would be super slow, so I dug it out with a decent amount of potting mix around the cutting and transferred that to a new container.

Everything was potted into individual containers using the same type of standard potting mix followed by a good watering. Voila! All done!

Front row (left to right): Golden Pothos, Ghost Plant, Jade Plant. Back row (left to right): Baby Rubber Plant and Variegated Baby Rubber Plant

 

By the way, that Wandering Jew that I had potted up back in October...well let's just say it's pretty happy!

A week later, and all of my new houseplants are enjoying their new home in my kitchen window.

 So, give it a try! Propagating these houseplants was pretty simple and definitely fun!

Adventure in Propagation

Posted by Sherie Caffey, CSU Extension-Pueblo County Horticulture Coordinator

Mother Fittonia

I’ve been into trying new things in the garden for most of my adult life, but one thing I had yet to experiment with is propagating house plants. I saw my perfect opportunity to give it a whirl when our office manager was trimming her Fittonia this Winter. I snagged two tip cuttings from her, did some quick research, and away I went on my adventure in propagation.

The ideal medium to use when propagating your houseplants is sand, vermiculite, perlite, or peat moss. I had some seed starting soil on hand, so I went with that, it was an adventure, after all. The tip cuttings I started with included the apex of the plant and two nodes. They were about 4 inch segments. 

I used small paper cups to start the cuttings. It is important to moisten your media before planting your cuttings. It was especially important for me as my medium had been under the sink in my office for who knows how long! After thoroughly wetting the medium, I buried the bottom inch or so of the cuttings in the medium, and firmed it so the cutting would stand up straight.  

Since new cutting do not yet have a root system, it is important to maintain very high humidity while they are in the process of rooting. To accomplish this, I placed a gallon sized plastic zipper bag over the plants. I blew air into the bags to puff them up, and I left a little space between the bottom of the bag and the plate the cups were sitting on to let a little air in. I misted them well with some room temperature water, which created a mini greenhouse environment for my new babies.

After a week, I started to introduce the plants to more air by using a hole punch to make a new set of holes every couple of days. It usually takes Fittonia about 2 weeks to produce roots. Once there is a one inch root the plants can be transplanted into larger pots. At the two week mark I transplanted them into 6-inch plastic pots. It was clear after a day that they were not ready to be out of the zipper bag greenhouse, so I kept the bags on for a while longer. I took the bags off during the work day for increasing amounts of time to try and wean the plants off of them.

By four weeks the plants were doing well without the bags for the whole work day, so I left them off for good. It has been just short of two months now and they are growing very well. Fittonia likes it humid, and I am starting to notice the leaves feeling a little dry. To remedy this, I will try putting the pots in trays filled with gravel, and water. It is important that the water is lower than the level of the gravel so your pot is not sitting in water constantly.

All in all, my plants are still alive so I am considering my adventure in propagation a successful one. Propagating your house plants is a fun and thrifty way to fill your home and office with lots of plants, I encourage you to have your own adventure in propagation!