Gloxinias
...a continuing feature...

I can't remember exactly when I fell in love with growing gloxinias. The image at right was taken in my classroom in 1996. By that point I'd been growing them from seed for some time. We actually had science classes hand pollinate the blooms using Q-Tips and saved viable seed which we grew the next year!

Gloxinias are relatively easy to grow from seed, but the plants take seven months from seed to bloom to produce flowers. The really great news is that once you have a mature gloxinia plant, it can live for years. As a rule of thumb, if you can successfully grow african violets, you can probably grow gloxinias. They both are members of the Gesneriaceae family. The care of the two species is quite similar, other than the gloxinia's required periods of dormancy.

Above is a composite of the gloxinias in my classroom that shows some of the variety in bloom colors and single and double blooms.

We start and grow our gloxinias under plant lights. Plant lights might actually be a compliment to the units, as they're really just some old fluorescent shop lights. I do try to use the 5600K bulbs when I replace them, but most any fluorescent should do. Once you get your gloxinias going, a sunny windowsill can be a good growing location. Ours at school sat in a west window and also benefited from the fluorescent lights and the cool nighttime temperatures in the classroom.

August 22, 2008

I start our gloxinias in shallow pots that used to come as reinforcement on the bottom of one and two liter soft drink bottles. Most any wide, shallow pot should really do for starting the seed.

It's best to use sterilized potting soil. I really don't trust the starting mixes sold in stores, as even if it leaves the factory sterile, a hole in the bag could admit damping off fungus, the bane of new plants. I just use a good potting mix with some peat moss and lime added and bake it in the oven at around 400^o for an hour to sterilize it.

For this feature I used a packet each of Empress Mix and Double Brocade Mix. I also started a pot of some very old saved seed that probably is a cross of Empress and Double Brocade.

The seeds are tiny. I've not come across a really good way to distribute the small seed other than just carefully tapping the seed packet or glassine envelope they often come in as I move my hand across the pot. There's no need to try to firm the seed into the soil, as it might stick to ones fingers and be lost. Just bottom water the pots.

Gloxinia seed does need light to germinate, so I set my the pots under my plant lights. The seed will germinate at room temperature or just a bit below in about a week to ten days. In the shot below, the germinating gloxinias share a flat with some fall lettuce.

September 1, 2008

The plants will appear as tiny specs of green against the potting soil when they germinate. I wait until they show their first true leaves before moving them into four packs.

September 17, 2008

Before getting into transplanting, I need to take a quick sidetrip here. Gloxinias form a bulblike structure at the base of the plant called a corm. "Corms are stems that are internally structured with solid tissues, which distinguishes them from bulbs, which are mostly made up of layered fleshy scales that are modified leaves." (credit: Wikipedia) As long as you don't try to split the corm, the distinction really isn't all that critical. But, you obviously don't want to break off or harm the corm.

To transplant, I use a small knife or plastic plant marker to tease the tiny plants and their fledgling corm and root system out of the soil. I do try to bring along the surrounding soil if possible. I make a small hole in the receiving cell of the four pack and drop the plant into it and gently firm the area around it. The transplanting process usually has to be repeated a number of times, as the gloxinias seem to germinate unevenly so they aren't all ready to transplant at once.

Then the freshly transplanted gloxinias go back into the flats under the plant lights. Let me emphasize here that you want to only bottom water your gloxinias. If you top water, you risk starting leaf rot, and at the very least, will have discolored areas on the leaves.

October 1, 2008

Also, I got my lights too low and bleached out some of this planting! I was trying to get the lights about an inch above the top leaves but now have backed them off to three to four inches above the plants.

I'm sure I lost some plants, but I also know some will rebound now that my plant lights are a bit higher. In the photo above, the healthy looking green plant near the top left extended beyond the close plant light and remained healthy from another, higher plant light.

October 30, 2008

After about 4-6 weeks in four packs, the some of the plants are ready to move to their final pot. Since the germination of the original plants is somewhat irregular at times, transplanting is also staggered a bit.

I generally use four inch square pots for gloxinias, although I also use six inch rounds for varieties I suspect may grow a bit larger. I'm still working my way through a couple of cases of pots I bought years ago when Mellengers was still in business, but some of the pots are becoming a bit brittle. (If you know of a good bulk supplier, let me know.)

I'm still pretty picky about the potting soil I use. Although damping off fungus is no longer a worry, I still use my sterilized soil mix of commercial potting soil, peat moss, a dusting of lime, and sometimes a bit of Captan. The Captan is to hold back any moss that may have gotten transplanted with the plant to its final pot.

I pop the gloxinias out of the fourpacks they've been in and plop them into a depression in the soil in the four inch pot. After firming up the soil around them, I bottom water.		After about a week under the plant lights, the gloxinia has recovered from the transplanting and is well on its way.

November 6, 2008

When I took the two shots of the gloxinia in its four inch pot, I was surprised to see through the camera's viewfinder an early bloom starting! I'd really planned to talk about pinching off blooms a bit later, but...

If you see a bloom starting at this point, harden your heart and pinch it off. You want the plant to put all its energy into producing a good sized, healthy plant. Pinching off the center growth area will also cause the plant to bush out a bit as well.

Once done, it's back under the plant lights for the various sized plants.

December 6, 2008

I transplanted the last of the gloxinias out of the starter "pots" today and also moved most of the ones in four packs into 4" pots. I knew I had to get this work done, as I have around 50 geranium seeds germinating over the heating pad that will need to go into four packs next week. (See: Growing Geraniums from Seed.)

December 20, 2008

Despite my efforts to discourage it by pinching off blooms, one of the gloxinias is now blooming. I got busy and didn't check the plants as regularly as I should have this month, only checking their moisture level.

The blooms will be a pretty addition when I move the plant upstairs, but obviously, the plant's energy is now split between growing foliage and blooming, where I'd rather it just be growing right now.

January 3, 2009

All of the gloxinias from the August sowing have now been moved to four or six inch pots. The eager beaver mentioned in the last posting now splits its time between a spot on the stove under a fluorescent light and on a sunny countertop in the kitchen. My wife, Annie, says it is one of the prettiest gloxinias we've had.

I'll probably try to start another round of gloxinias sometime this spring for late fall potted plants. That's a very busy time in the garden and under my plant lights. But it's also just the right time to start gloxinias for September and October blooms. So, I'm going to make an effort to find the time and space for them under the plant lights. Note that I rarely put gloxinias outside in the summer. They just don't seem to do as well as they do under the plant light. But when space gets tight...

You might wonder why I'd consider starting more plants in the spring when I currently have ten healthy gloxinias. Over the years I've found that friends and visitors to our home (and in the past, to my classroom) generally oohed and aahed over the plants. When given one, they were absolutely delighted. I expect our gloxinia population to begin to dwindle as the plants come into bloom, and they are adopted out to good homes.

As the rest of the plants come into bloom, I'll begin hand pollinating the blooms, tagging the pollinated blooms (usually with just a loosely attached twist tie), and collecting seed once they dry out.

January 16, 2009

Our one blooming gloxinia finished its early bloom cycle and went back downstairs under the plant lights this week. Hopefully, it will now add foliage and build its corm before blooming again.

When I was uploading some video to YouTube to illustrate the Brinno GardenWatchCam, I ran across a video labeled "Flower Bloom." I think the video is from the camera's manufacturer, but how delightful (for me, at least) that the flower blooming was a gloxinia!

January 20, 2009

I really wasn't thrilled with the gloxinia offerings on eBay, but I succumbed to the temptation last week and ordered several packets of gloxinia seed. The seed was packaged in small plastic bags, which made it very difficult to seed. The dustlike seed clung to the the sides of the bags, so I had to cut them open and wash the seed off the plastic into the planting pot.

So, even though I already have nine or ten healthy gloxinia plants under my grow lights, there are 30 seeds in the pot shown above.

February 12, 2009

The gloxinias seeded in January are just beginning to germinate.

Our August sowing is coming along nicely. Three of them that are currently in bloom are sharing kitchen counter space with all the other items there. From left to right are an Empress, a Double Brocade, and a speckled blooming gloxinia from saved (and crossed) seed. When the sun fades, the gloxinias are moved onto the stove (when clear) under a fluorescent light.

It appears the gloxinias are putting up one or two early blooms before returning to growing leaves and adding to their corm. As they finish this early blooming cycle, I return them to the plant rack in the basement under our plant lights.

I noticed the leaves on the gloxinias in the basement were yellowing a bit. I began top watering with some dilute fertilizer that contains extra iron, but also switched one bulb per fixture to a new 6500K (daylight) fluorescent tube. The remaining old fluorescent tubes are 4100K, which probably was the problem. I've noticed immediate improvement.

February 14, 2008

At this point, you might wonder why I go to all the trouble of growing gloxinias. It does take a long time from seed.

Below is a photo taken in my classroom in 1996 of a Double Brocade gloxinia. I think the picture easily answers the possible question above.

April 14, 2009

I'm getting a bit behind on this feature, but I haven't been neglecting our gloxinias. Several in turn have produced blooms and come upstairs for their duration. It appears our plants are putting out one or two tentative blooms before returning to building leaves and corm. When I return the plants to our plantlights in the basement, I try to make sure to add the bloom color to the plant tag in each pot.

Since both our planting and the seed's germination were staggered a bit, I have plants in various sizes. I just moved the last three plants out of our cokebottom seeding pot into a fourpack this week.

I've moved each of the gloxinias into four inch plastic pots when they're ready, although many have required a move to a six inch square pot later. The frequent moves have also helped me get away from a dreadful potting mix I used early on.

Here are the four inch square pot bunch. As you can see, I'm having some yellowing that repotting and/or fertilizing, plus watching moisture levels seems to correct.

Some of the gloxinias above have been moved to six inch round pots. The Empress variety almost always produces a larger plant and requires the larger pot. Notice the two gloxinias in the white, four inch square pots will need a larger pot soon.

A couple of the plants that have already bloomed once are putting on multiple buds and should be free flowering soon. If you're keeping score, it appears that the first bunch will be in full bloom about eight and a half months after seeding.

May 3, 2009

It's been eight to nine months from seed, but we finally have our first gloxinia in full bloom. We've been tantalized over the last few months with plants with one, two, or three blooms, before they stop blooming and begin building foliage and corm again.

The gloxinia pictured below has six open blooms with at least seven or eight more showing. I'm sorta proud of it, as it's one of our gloxinias from saved seed, rather than from seed I purchased.

It's probably time for me to get some more gloxinia seed started for full blooms next December or January. Of course, I'll still have my current plants (if I don't give them all away as I'm prone to do at times), but I'd like to get back to glorious displays such as the one pictured at the top of this feature.

May 15, 2009

I seeded three more "pots" of gloxinias on May 6 and was pleased yesterday to find lots of tiny gloxinia seedlings emerging. Unfortunately, I tapped my seed vial over one of the pots a bit too hard and ended up with a clump of seed in one spot. I tried scooting it a bit, but as you can see at right, the plants and the reddish-brown seeds are way too close. I'll lose some plants from crowding, but will transplant the survivors as early as possible.

Still to Come: Pinching, Dormancy, Leaf Cuttings, and Saving Seed

I've been taking things pretty much in chronological order in this feature. Some readers may be way ahead of me and have questions about pinching off plants, how to treat gloxinias as they enter and emerge from dormancy, how to replicate plants via leaf cuttings, and/or how to pollinate and save seed from them. I'll get to each of these issues as we get there. And, I've purposely avoided talking about pinching off plants to make them bush out better, as I'm really not very good at it.

If you have questions before I get to this stuff, write.

September 11, 2009 - Saving Seed from Gloxinias

We're now getting some good amounts of seed from our gloxinias. I did a posting on my Senior Gardening blog about it today. I'd planned to put the information here, and will, eventually.

I wasn't happy with the sharpness of some of the images of the seed in the flower ovaries (at left), so I'm waiting on some close-up filters I ordered before redoing the photography for the update.

October 10 , 2009 - Saving Seed from Gloxinias

I finally got some better images of pollinating gloxinias. The task took a digital SLR with manual focusing capabilities, a better lens than the "kit lens" supplied with the camera, a set of macro close-up filters (instead of a far more expensive macro lens), and a good tripod. But at long last, I've put up the seed saving information on a separate page, Saving Gloxinia Seed.

Most of my gloxinia plants are headed towards dormancy, so that will probably be the next topic I'll cover here. If I can, I'll also snip a few leaf cuttings for propagation and document that process here as well.

March 18, 2010 - Creative Pinching

Years ago, you used to be able to send gloxinia plants from local florists. The plants delivered often had masses of six to ten blooms in the center. It made for a fantastic gift.

One of our last gloxinias to come into bloom this blooming period had a number of buds trapped under its leaves. There really was no way to gently guide the buds past some new leaves in the center of the plant, so I just pinched off the leaves, leaving an outer ring of older leaves with the buds and blooms in the center unimpeded in their upward growth.

I think the florist gloxinias of old were probably second year plants, but I'm hoping to achieve the same effect with my first year plants with the creative pinching.

Update (4/6/2012): Don't be afraid to pinch back the center of young gloxinias from seed once they get several, say four or more, true leaves on them. Pinching out the growth center will slow the young plants down a bit, but will also make them spread out with more stalks...which means more blooms eventually.

March 31, 2010

As I saw the cluster of blooms maturing on the plant I pinched off a few weeks ago, I cut off the existing blooms to allow the plant to put all its energy into a big splash of blooms. My wife was a bit disappointed, as the cut blooms really hadn't begun to wilt all that much. But the result was just what I wanted. In just a few days, the plant put up six new blooms with more on the way.

While this isn't our prettiest gloxinia, it sure is a nice addition to our kitchen window. And, this was from a first year corm. Gloxinias that are in their second or later years can produce really dazzling clusters of blooms, as their corms are much stronger.

Saturday, December 24, 2011 - Surprises

While watering our gloxinia plants this week, I saw what I thought was a bit of moss growing around the base of one of the plants. Reaching to rub out the moss, I quickly drew back in surprise. It turned out that two of our plants had lots of baby gloxinias growing around them!

I didn't spill any seed on the pots, nor do I reuse potting soil without first composting it and then sterilizing it in the oven. So the seeds didn't come from either of those two possible sources.

I really haven't given our gloxinias the care they need this fall, having concentrated more on outdoor gardening and home repairs. I recently cut many of the plants back a good bit and also have quite a few entering dormancy.

The cutting back of ragged and dead foliage made possible my "discoveries." Apparently, the plants had somehow self-pollinated (not too many bees in our basement), and I simply didn't notice. I'd been too busy with other stuff to do much more with the plants than their weekly watering. When I finally did get the plants cleaned up, there were lots of spent bloom to pick off. I never noticed any seed bearing stems, but I was going pretty fast when I cut and pinched off the old growth and blooms.

I pinched off a few more leaves today that may be shading the baby gloxinias. It shouldn't hurt the existing, mature gloxinias, as they are pretty well on their way towards their required period of dormancy.

When the tiny gloxinias get just a bit larger, I'll transplant them into fourpacks or 3" square pots.

Dormancy (Updated 4/8/2011)

After gloxinias go through a blooming cycle, at some point the leaves will begin to wrinkle and possibly even yellow a bit. When this happens after a good blooming period, it's time to cut back on watering the plant and stop fertilizing it. The plant is heading into a required period of dormancy. Fertilizing, repotting with fresh potting soil, and frequent watering will force the plant to produce leaves (and possibly a few blooms) until it dies! As the leaves of the plant wither, just pick them off until there's nearly none left and move the plant to a dark, cool place and let it sit. In several months, you will see tiny leaves emerge from the plant corm. At that time, repot the plant, or at least add some fresh potting soil around the edges of the pot, fertilize, and move it back into the light to begin another growth and blooming cycle.

After five or six of our plants broke dormancy over the winter in 2011, I began to wonder if I had become "the great gloxinia killer," as some twenty or so other dormant plants sat and did nothing for the next three months. When I moved all of our spring garden transplants outside in April, I noticed first one, no two...and finally, about a dozen of the previously dormant plants had put on tiny shoots and leaves. Whew!

Sadly, some plants never emerge from dormancy. If it's your one prized gloxinia, that's pretty bad. We now have dozens of gloxinia plants in various stages of growth, so losing one or two isn't a tragedy.

The late James Underwood Crockett wrote in Crockett's Indoor Garden (out of print now, but still available used from Amazon) that "there is absolutely nothing complicated about handling a gloxinia during its dormancy." He adds that "gloxinias can live for years - fifty-year-old plants are not unknown."

Of course, he proceeds to tell the following somewhat humorous story:

I remember once selling a gloxinia from the flower shop that I owned in the late 1940s. I explained to the buyer that the plant needed dormant periods after each flowering, and told her how to care for the plant during each part of its cycle. Her eyes glazed over, her brow furrowed slightly, and she left my shop with what I knew to be a doomed plant.  

Leaf Cuttings (Updated 4/6/2012)

I've certainly taken my own sweet time in getting this last piece of essential gloxinia culture published. The reason for the delay is that I don't reproduce many gloxinias by leaf cuttings. I really prefer the experience and surprises involved with growing them from seed (especially open pollinated seed that may produce all sorts of blooms).

But I got busy last November (2011) and took three leaf cuttings from a very pretty gloxinia while taking some cuttings from a couple of our ivy leaf geranium plants. I'm just putting this section up now, as the last two of the three leaf cuttings have finally produced baby gloxinia plants.

When reproducing gloxinias from leaf cuttings, it's important to remember that what you're creating is pretty much an exact clone of the plant from which the cuttings are taken. Don't expect to get velvety red blooms from cuttings taken from a purple blooming gloxinia plant. It's not going to happen.

The first step is to find a healthy gloxinia you wish to reproduce that has some small to medium sized leaves. For leaf cuttings, you don't want the jumbos that gloxinias in full bloom often produce. Select a two to three inch leaf that with its stem (as much stem as you can get) isn't over about four inches long. Just use scissors to snip off the leaf at its base.

I trimmed a leaf or two off the plant shown here to expose the leaf to be cut. Without doing so, you have to worm your scissors through the plant growth to get to where you want to cut.

Don't get too hung up on leaf size. A little bigger or smaller certainly won't hurt anything. And...I went back and shot new photos of taking the cutting(s) today, as my original shots really stunk! I didn't measure the leaf to be cut, but when I put it down on the tape measure, son of a gun, it was almost exactly four inches long.

At this point, you need some supplies to aid your leaf cuttings in rooting. You'll want some rooting hormone and sterile planting medium along with pots or other containers. I used some powdered Rootone I had on hand for the cuttings I took in November, but Hormex or the newer and much more expensive Clonex rooting compound gel will do the job. I think my rooting powder was too old, which caused our cuttings to take a long time to root. But that also may tell you something about the necessity, or lack thereof, for using rooting gel. Since taking those cuttings last November, I did buy some of the rooting gel for a cutting from my wife's favorite geranium that had developed a woody stem, and the precious cutting rooted in just a few weeks! So, it's probably better to use rooting compound, just not very old, probably outdated stuff.

If using a powdered rooting hormone, dip the stem of your leaf in water first and then into the powder. If you're using rooting gel, just dip the stem in the gel.

Make a slanted hole in your planting medium and insert the stem right up to the base of the leaf. Firm the sand, soil, or whatever medium you use over the stem. Then the whole pot with the cutting should go under something to hold in moisture until some rooting begins. I just pop my cuttings into a plant flat with a clear, humidome cover. Note that when I got pressed for space some weeks ago, I took the last two leaf cuttings out from under their humidome, and they still rooted. But at first, the cuttings will need something, even a clear plastic bag that doesn't touch the leaf, to hold in moisture and allow light in.

As I mentioned earlier, when I took the cuttings in November, I was also taking cuttings of some ivy leaf geraniums. At that time of year, there's not much competition for our plant heat mat, so I popped all the cuttings onto the heat mat in a tray with a clear cover. Bottom heat really isn't necessary for rooting cuttings, but in moderation, it can't hurt.

Note, if you click on the image at right for the larger image, the temperature shown (86.9^o F) is because I bottom watered the tray with warm water. My thermostat was set at 75^o F.

Don't give up if your leaf begins to brown in spots and shrivel after about a month. The nasty looking, shriveled leaf shown at left, when turned around (below at right) is producing a baby gloxinia plant. Instead, continue to watch it closely, because a new plant will probably begin to emerge shortly thereafter. From our November cuttings, we had one baby gloxinia emerge in mid-February. I didn't notice the other two plants until today, April 6. I have no idea why the different leaves took differing times to put out baby gloxinias, but was pleased that all of the gloxinia cuttings I took rooted and produced new plants.

All of the above may seem like a lot of trouble, but with gloxinia plants and corms going for over $10 each, replicating plants you like really is a good deal. From cutting to bloom, it's supposed to take about six months, as opposed to from seed to bloom which runs around seven months.

And while they're all still small, the images below are the result of the three leaf cuttings I took in November.

The plants above all came from cuttings from the purple gloxinia shown below. And to demonstrate the use of the rooting gel, I did take a couple of cuttings today from the red gloxinia in the same photo. I fully expect to have some absolutely gorgeous replicas of the the two gloxinias below in just a few months.

Where to Buy Gloxinia Seed, Plants and Corms (updated 4/6/2012)

The Empress gloxinia seed for this project came from Stokes Seeds in Buffalo, New York. A packet of 25 seeds runs just $3.25. Stokes ships to both the U.S. and Canada. If you're just getting started growing gloxinias and/or indoor plants, it's the one to start with.

The Double Brocade hybrid is available from Thompson & Morgan Seeds. My initial Double Brocade seed came from Park Seed, but they dropped the variety several years ago. Thompson & Morgan sold its U.S. division a year or so ago, but the new outfit still carries the seed (tmseeds.com), although it only ships to U.S. postal addresses. Folks in the UK can still get several gloxinia varieties from the original Thompson & Morgan (thompson-morgan.com).

There generally are listings on both eBay and Amazon for gloxinia seed, but you might also want to check out the sellers' ratings at Dave's Garden before ordering!

Gloxinia plants are available from The Violet Barn (thanks to Steve Paige for that info). Plants run $5-10 each plus priority or express mail shipping. I placed a test order in May, 2011, and received two tiny, but healthy gloxinia plants wrapped exceptionally well for shipping. Sadly, I broke the stem of one plant in my eagerness to get the packaging open, but may end up with several of the variety, as I used a bit of Rootone and some pots of sterilized growing medium to start cuttings from the damaged plant.

The Violet Barn also has outstanding ratings on the Garden Watchdog on Dave's Garden.

Note: I don't sell gloxinia seed, corms, or plants. I have, on occasion, traded seed with other growers. One very positive swap was with John Rizzi from California, who sent me a generous sample of Cranberry Tiger gloxinia seed in exchange for some of our open pollinated seed. We've had magenta, white, and purple blooms so far from our first planting of his seed. (The rest is in our freezer.) I noted in a March posting on Senior Gardening:

While the blooms on the Cranberry Tiger variety are slightly less spectacular than our usual Empress variety, its foliage seems to hold up much better in our growing conditions. I'm quite impressed with the new (to me) variety.

For a long time, I couldn't find any U.S. vendor selling gloxinia corms. In March, 2012, an exchange with a reader produced a possible vendor. Nature Hills Nursery sells four varieties of gloxinia corms. I placed an order as soon as I heard of them, ordering all four varieties in a discounted assortment group. While discounted, they weren't cheap, running a bit over $40 for the four with shipping. (Individual corms run $9.99 each plus shipping.) When the corms arrived, they appeared to be of good size and in good condition, although a little dried out. Sadly, three of the four corms were bad, and to make matters worse, Nature Hills put me off with no offer of a refund until I eventually spoke to one of the co-owners of the nursery. I mentioned the beating Nature Hills was taking on Dave's Garden Watchdog over bad stock, poor customer service, and an apparent policy of stiffing customers for bad plants. I got an apology and the promise of a refund, but only after I'd revealed myself as the author of this page and site. And what I really wanted were Emperor William and Emperor Frederick gloxinia plants...without any hassles.

It takes seven months, more or less, for gloxinias grown from seed to flower, but the payoff is well worth the effort.

This feature on Senior Gardening isn't complete by any means. But after years of growing and enjoying gloxinias and years of writing on the web, I realized that I'd never done a whole piece on these gorgeous and easy to grow plants. Rather than wait until the project was done, I decided to put up what I had and come back later to finish.

From the at Senior Gardening