How to heat a greenhouse

December 18th, 2017

So I’ve planted my greenhouse and I have things growing. I do not yet have my automatic watering system setup yet, I have drip irrigation run to about half of it, but it isn’t automated. The humidity stays so nice and high in there though that watering needs haven’t been too bad.

I planted some morning glories for color and interest, beans, beets, cabbage, kale, sweet potatoes, lettuce, spinach, purslane, sugarsnap peas, peppers, some herbs, and I also have some citrus trees growing. A blood orange, a tangerine, a lemon, and a lime. Plus an avocado tree I started from the pit.

The veggies are mostly cool weather crops, but the citrus needs warmth, and I have been worried about maintaining the heat in my greenhouse at a minimum of 50 degrees lately. We had some cold weather here in Chattanooga and I’m up on a mountain.


So originally I was going to do a heated floor in my greenhouse, and I guess I could have. I was going to do it all through my first floor. Radiant heat like that is supposed to be so nice and efficient, but it became a cost problem. Essentially I would have to put in two systems, one for heating, one of cooling, which increases the overall expense. I would also need to invest in a concrete subfloor for my 1st floor (which is above a basement) which is a whole lot more expensive than osb. So I kicked that plan to the curb earlier on. I thought I would put a wood stove in my greenhouse where I could just start a fire on the coldest nights. That would be doable, but I cut that as well. The chimneys and all that were adding to my cost, though in retrospect it may have still been economical. Our plan for the house changes to be a zoned split system that pumped refrigerant around to air handlers, I could have put a dedicated air handler for that in the greenhouse but each zone was quite expensive. Then I thought I would get a propane boiler (we don’t have natural gas) to do my hot water and I could do a side system off that to heat the greenhouse with a radiant baseboard, and that was the plan for awhile, but then we kicked that to the curb as well and just got a straight propane water heater (well, 2 of them). But in the meantime the refrigerant plan with the HVAC went away and now our HVAC system works similarly only it sends hot and cold water, so I could have used radiant pipes in the floor had I not already poured the slab….


So what I did was install a radiant baseboard that was connected to hvac system. It wasn’t cheap, over a grand in materials plus labor. And you know what it provided? Next to no heat, 1000 BTUs or something an hour. That is nothing. The problem is radiant heat is meant to work off a boiler, off water 180 degrees+, my hvac system uses water more like at 120 degrees or less. This wasn’t producing the heat. The baseboard helped, but was not able to keep up.


Then I stumbled upon this really cheap hydronic (that is, using water) air handler on eBay (I think I searched for greenhouse heater). For like $200 I got a 100,000 btu air handler that is hung from the greenhouse superstructure. I wish I had known this thing existed before. It isn’t pretty, and I don’t imagine the fan is that efficient, but it works great so far for my greenhouse. For the baseboards I already had the hot water lines run so it was just a T and 7 feet of pipe to hook up this thing. It comes on if temperatures drop to 50 or below and produces a good volume of warm air while also providing circulation. I would have saved quite a bit of money had I known about this thing in the past. Apparently it is also good for garages and warehouses.


I have a pretty high end and insulated greenhouse. The foundation is insulated concrete forms, the glass is insulated low E stuff, it doesn’t need much heating, especially if it gets sunny. But on the nights after days where the sun is never seen it does need help, and this apparently will do the job.

Harvesting Sweet Potatoes

November 17th, 2017

I am finally moved into my new house after years of construction (its still not done and we’re at more than 2 and a half years since breaking ground) and even more years of planning, and hopefully soon I can get back into my garden more frequently now. Being without a proper garden all this time has been hard on me. I had then put up this garden I think 2 years ago now, but not living up at our build site I couldn’t really deal with it.

So I mostly grew weeds, and some tomatoes, and some other things, but mostly weeds. This year was worst than last year. Last year I actually managed to come up more and do some weeding, and there was also a drought. This year there was plentiful rain and I had less opportunity to come up and deal with weeds. I settled for simply putting plastic straight over some large sections of the garden to kill the weeds but they just grew out of control in other sections or too big for the plastic treatment (my garden is 5000 sq/ft, it is a lot to handle 15 minutes at a time). The weeds grew taller than me because of all the rain, and most regretfully they were able to go to seed before I could do anything like kill them or till them under. I hate it when this happens, allowing a weed to go to seed is a cardinal sin of gardening. I fear next year I will have it even worse.


Right now my plan for next year is to landscape fabric the whole entire thing, and poke holes for planting. That is the only thing I think will truly allow me to get a handle on my weed situation.


The only thing that truly grew well for me was sweet potatoes. I planted I think 25 sweet potato slips. I had tilled the section and then immediately planted the sweet potatoes and thanks to the regular rains and hot humid weather they were able to grow enough to shade out most weeds in that area. I still got some tomatoes, not as much as last year, and some peppers, some beans, and the kale is out there still growing strong enjoying the colder weather, but I got so, many, sweet, potatoes.


This was my first time successfully growing them, I had tried a few times in the past without much luck (but often in Michigan where they aren’t well suited, here now in Tennessee it is a different story). I got I think 300 pounds of them. I completed filled a large two wheeled wheelbarrow and, despite being quite a strong man, could barely move it. They have been curing a week and a half in my greenhouse (it gets cooler at night but is otherwise the only room I have that can get up to 90+ during the day which is what sweet potatoes need I’m told). I’ve lost a few to rot, likely already rotting before harvest. I’m also sure I missed some still out in the dirt. They are supposed to cure for 2 weeks then go somewhere into long term storage (still dry and relatively warm), so I haven’t tried any yet. But sweet potato casserole is calling come Thanksgiving.


So once the curing is done my family could eat a pound a day and have them last nearly a year. I never really felt like I could truly feed my family off my land until now. But now I think that my garden is capable of providing enough food for that (plus all of my fruit trees and whatnot) and add in hunting in our forest I think we could really live off the land. Not that we need to in our modern society, but there is something primally rewarding about the notion that it could be done.


In furtherance of that belief I am trying to maintain my sweet potatoes. One tuber I dug up still had small plants attached to it, so this one is already potted up in my greenhouse. There were also many small potatoes I found that won’t be great for eating but I have them half submerged in cups of water to generate more slips. If I can get slips off of these I will plant them (I also bought a 200 gallon fabric pot for my greenhouse for my winter sweet potato patch), and experiment with growing sweet potatoes year round. I don’t much want to be able to generate a large harvest here in my greenhouse, it would be nice but I’m realistic about it. My main goal is to just make sure I have live sweet potato plant material come late spring so I don’t have to order slips or make my own off a store bought sweet potato. I want to have a greenhouse full of sweet potato vines I can divide and root and transplant out in the garden, not just little slips, but healthier larger vine segments, “super slips” if you will, to get a start on the next season and provide the missing link in true self sufficiency. I would like to thus prove to myself that if cut off from the rest of society I could continue to grow these perpetually with my setup.

I will let you know how it goes. I also just learned that sweet potato greens are edible and nutritious, so I might nibble on those over the winter as well.

My biggest concern, both with my curing and my overwintering, is the temperature swings in my greenhouse. It gets up to 95 or 100 degrees if the sun is shining, but at night it can drop to 60. It has a heater but the heater is not capable of keeping it very warm at night. Humidity is no problem. So I’m not sure if this is going to consistently provide the summer mimic temperatures for the potatoes to thrive or if it will be too cold at night. I’m also not sure what the swinging temperature will do to my curing process. This will be an experiment for sure.

Weeping Blue Atlas Cedar, Cedrus atlantic ‘Glauca Pendula’

May 4th, 2017

I’ve been pining after a weeping blue atlas cedar Cedrus atlantic ‘Glauca Pendula’ since I first saw it on Paul James’ Gardening by the Yard way back when. It is hard to put into words what I like about it, or all the cedrus. I remember it being one of Paul’s favorite trees so maybe his enthusiasm rubbed off on me a little bit.

Overall I enjoy this species because of how the needles are presented, maybe. The needles are not long like a pine, nor do they fully cover the branches, like a spruce. Instead they are held in tufts, and this leaves a large amount of the structure exposed which then allows you to appreciate the architectural nature of the trunk and branches. The weeping form of course has very interesting structure. Left to it’s own devices, like many weeping plants, it would grow prostrate along the ground, the wood cannot support the foliage or itself until it is several years old so it requires training as it grows, training into whatever interesting shape you want, and then the side branches will all droop down like old moss clinging to something, it always evokes a prehistoric feeling in me.

So when I lived in Michigan I couldn’t grow this. I had seen some people try to make it work, with a microclimate, but even the one nursery nearby that sold any recommended against it (and said they sometimes would lose inventory to the cold). Hardy to zone 6, they just weren’t going to cut it in zone 5 where I lived. But now I live in Tennessee, zone 7, and it was high on my list when I moved down here. I finally saw one at a Lowes and picked it up.

My Weeping Blue Atlas Cedar

I planted this on a berm near the driveway of my future (under construction) house. Right now I just want it to get established, which is hard because my little corner of the world is (was) having an epic drought. Eventually I will figure out how I want to train it. They get really pretty when they get big, you can make an archway, or like a big leaning dinosaur like thing. They’re just very architectural with their branching.

The below picture is a good example of a smaller tree.


Then this picture is a good “creeping dinosaur” example of a mature tree.


Great Flowering Groundcover: Homestead Purple Verbena canadensis

April 27th, 2017

I have always liked flowering groundcovers, something about a carpet of blossoms just does it for me. Plus the more ground covers I have, the less mulch I have to buy.

When I lived in Michigan my go to was creeping phlox, which I had planted all over my yard like in the below photo. It spread reliably though not super fast, bloomed like mad in the Spring, and the foliage was not unattractive… and yet it bloomed like mad in the Spring only, no other time.

Creeping Phlox Emerald Blue, Back Garden

Creeping Phlox Emerald Blue, Back Garden

Now that I live in the South I still like creeping phlox, and I drive by this home regular that has a whole front slope covered in it and it looks great, but I’ve been trying to get it going and not having as much luck. Meanwhile, I’ve discovered verbena, something not hardy up in Michigan. I can buy it down here at Lowes for 5 or 6 bucks for a gallon pot, less when it’s on sale. I recall buying maybe a 3 inch pot last year for maybe $2.

So I planted this one solitary plant late last summer. I spent all summer trying to find it, I had read about verbena, thinking it was the plant for me (even deer resistant! which is important, because organic free range venison has been getting all up in my business), and couldn’t find it, mail order nurseries were all sold out, then I go to Lowes one day and boom, trays and trays of it. I buy one I think, to give it a try. I planted it early last Fall, witness below:

Newly planted Homestead Verbena

Newly planted Homestead Verbena

Cute, but small, yes? Not really florific yes?

We had a drought late last year, really really bad, extreme on the USDA drought map, many of the plants I planted alongside this verbena did not make it (I planted it where I’m building a house, not where I’m living, and so it wasn’t able to get reliably watered). The verbena not only survived that drought, it thrived. Winter came, then here, in Spring, look what this plant has done:


That is the same verbena, two seasons later, not two growing seasons later, two seasons, call it 6 months. It did that in 6 months. And those flowers, and they’re still blooming strong. That is why I think this will be my new favorite groundcover, it blooms from early April until November. My understanding is that the blooms will lessen later in the summer and I can deadhead or cut back to encourage more heavy bloom flushes, but still, blooming at all for that long of time, and drought resistant, and deer resistant. Sign me up. It is taller than creeping phlox, getting up to 8 inches or so in height.

I like this so much I planted a bunch at my business too, and bought more for the slope where this first test went, and I think I will get more still.


The plant will spread, which of course you want it to do as a ground cover, rooting where it comes in contact with the soil, and it is also easily propagated from cuttings. It needs sun for flowering, the more full the sun the better.

Vibrant Variegated Holly

September 24th, 2016

Recently on a Saturday between kids birthday parties I had some time to kill so wandered over to a nearby Lowes to look at the plants and I’m glad I did. I shop a lot at Lowes and Home Depot but generally their plant selections aren’t too great, especially the sort of stuff I like, but every once in awhile I get lucky, and I should say Lowes here had a much better selection of what I like than Home Depot, and I still haven’t found a really great local source for what I like (rare interesting conifers).

So I got lucky and picked up three trees, a weeping blue atlas cedar which I’ve wanted since I saw it on Paul James all those years ago, but could never grow before because where I was in Michigan it wasn’t hardy. A vibrant blue upright juniper, which I’ve grown before and I love it as an accent landscape planting, and finally, the one I want to talk about today, a variegated holly.


I had quite frankly never seen a variegated holly before. Overall I’m not a fan of regular hollies, they just don’t do it for me, I think they can end up looking sloppy. I do like the columnar varieties like ilex ‘sky pencil’ though. I see the value in them for the red berries which can be bright and food for wildlife, but I can’t see myself growing a plant just for decorative berries.

However, add the variegated foliage to the mix and I got really excited about it. Not just dark green and red, but dark green, yellow, and red, so much more interesting. Mine of course doesn’t have berries, not yet, but when it does it will look attractive.

It is also nice because while it may feed the birds, it doesn’t feed the deer. The spiky leaves are generally immune to animal browsing, and in my new garden there is definitely deer pressure.

I’ve planted it in the front ornamental garden (in progress) of my future house (in progress). My overall goal with this garden is to make it a cacophony of contrasting foliage plants, similar to a Japanese style garden but not limited to Japanese plants. Flowers are all well and good but a vibrant blue evergreen will be blue all year round, and my hollow will be yellow and green all year round. These are my favorite sorts of gardens and so of course I want one for myself. I will be a showcase for the wide variety of rare dwarf conifers I hope to cultivate,, and this holly will make a nice focal point.

Sunscald: White rot on the sides of my peppers

September 18th, 2016

I am learning a lot of new things gardening in a new state. Including something recently. I really like growing peppers, all kinds, I think they’re relatively free from pests and diseases (especially hot ones) and we eat a lot of peppers. Bell peppers are one of the few vegetables neither kid complains about.

So I planted a lot of peppers this year, and they grew well, but I’ve had crap for yield, they keep rotting on the plant. They’ll get this spot, and it’ll be yellowish white, then it’ll turn more white, and then it’ll get bigger and bigger and bigger. It looked to me like some sort of fungal infection.


I finally looked it up, this isn’t a pest or a disease, but the effects or heat and direct sunlight. In Michigan we always worried about peppers getting enough heat and sunlight, apparently here in Tennessee-almost-Georgia its the opposite. Too much heat and too much direct sun causes the flesh to simply get scalded away, and then it does become an avenue for infection, and the fruit rots. I was glad to find out the cause wasn’t going to require fighting another infestation, but I’m not sure a good solution. The leaves need sun to develop large fruit, but the fruit needs to be as shaded as possible. Fruit socks anyone?

This also happens to tomatoes which explains why I had these whitish gashes on them as well. Although for those, since I basically make sauce with all my tomatoes, I just cut off the damaged portion and still used them.


It is probably extreme this year. Last year around this time it was far more rainy and cloudy down here. This year we’re in the midst of a drought and rarely even have an overcast day, let alone rain. We’ve had one overcast day, the only one with rain, in the past 4 weeks. Lots of plants are dying, trees are dying, the drought stress is significant. I’m keeping my finger’s crossed for rain tomorrow, it is in the forecast.

In the meantime I will water my peppers and maybe try moving them (many are in containers) to where they get morning sun but afternoon shade.

I don’t mind spots on my apples, but save me the leaves, please: Apple-and-thorn skeletonizer Choreutis pariana

September 3rd, 2016

We’ve been having a drought here, and up where my house is being built my fledgling fruit orchard is not doing super great, just not the sort of summer where they’re going to put on a big fat growth ring.

But a few of my apples, specifically my Honeycrisp, are doing particularly bad. They’re invested with something. Two have damage on every leaf, and have lost many leaves, if it continues unabated I could lose the trees.

The leaves are skeletonized in a very very fine fashion, more fine than like what japanese beetles will do. There are also bits of webbing, curled leaves, and black debris that is either droppings or eggs.






I believe what I have is an infestation of Choreutis pariana, or the apple leaf skeletonizer, or apple-and-thorn skeletonizer. It is a little moth, an invasive species from Eurasia introduced in 1917. It is a tiny little moth only about a quarter of an inch long. It’ll hit apples, crabapples, birch, cherry, hawthorn, willow, and ash. It’ll lay the eggs, the pupa will hatch and eat my leaves and poop all over and curl the leaves and leave bits of silk, and then turn into a moth and start all over again with a 30 day life cycle.


Luckily it looks like they can be controlled with Sevin and similar pesticides. I don’t really like using these products, especially on a fruit tree, but this IS an invasive species, and I don’t have any apples on the tree currently, and if I don’t do something I may never have any apples. So. these bugs have a date with the sprayer.

The truth about those expandable hoses

July 31st, 2016

I’m sure we’ve all seen this commercial, you turn the water on and this hose grows, stretching to where you need it, you turn the water off, and it shrinks back, neatly putting itself away.

It does not actually work like that.

I was given this hose for free to try out, and now I get to let you know how it went.

Expandable Hose

So, the outer canvas wrap is mostly for looks, it doesn’t seem to serve a purpose (but it does, read on), instead there is some sort of very stretchy rubber hose on the inside. It does stretch, but more in girth than in length. As it fills with water pressure builds up inside and the rubber inner house expands, as you spray water out of the house pressure is relieved and it shrinks. The canvas wrap is there as a backstop, to prevent it from expanding too much, and bursting like a balloon. Picture a balloon inside of a pillow case.

So you turn it on, it expands slightly (I would say no more than 20% in length), and use it to water. Then you turn the water off, and it shrinks…. nope! It doesn’t, you can turn the water off but so long as pressure is still inside the hose it will not shrink. After you turn the water off you need to run the hose for some time, I would guestimate 30 seconds, in order for it to shrink back down in size.

The house does not take standard fittings, it came with it’s own fittings, and they seem nice and are quality enough, but in the end, the “expandability” is a gimmick. This hose certainly functions as well as any other hose, but I don’t see much use in the expandability, at least in the garden, because something that stretches in girth is not helping us keep our hoses neat and tidy.

Where I can see a use is if you need to pack the hose away, or travel somewhere with it. That a very long hose can fit into a little box is certainly useful, and overall it is lighter as well. You could certainly more easily tuck it away into a planter or something. this 100ft hose came in a box about the size of half a two liter bottle, and it included a spray nozzle in the same box, that is really small, a standard 100ft hose is big and bulky to carry, and may even be too heavy for many people, this is light.

So, buy it if you need a hose that can be stored in a small container, or a lightweight hose of reasonable length, don’t buy if the commercials gave you the same impression they gave me, that of a hose that more or less puts away itself.

How to start and grow new sweet potatoes

June 28th, 2016

I’ve been working on this post for months, because it is a months long process. Taking pictures along every step of the way, documenting the process. And then I lost a ton of pictures. I used some recovery software and was able to get some of them, but not all, so there are far fewer pictures in this post than I originally intended.

To grow sweet potatoes you don’t use seeds, you use slips, which are tiny sweet potato plants. To make these slips you need to put a sweet potato, or pieces thereof, into water for weeks. Roots will come first, and later sprouts will come out. There are two main ways to do this.

1. Whole Potatoes

I recommend buying organic sweet potatoes, or from a farmer, or use ones left over from your last harvest, because some store bought potatoes may have been sprayed with something that inhibits sprouting. Weirdly shaped ones work well. I used old pasta sauce jars and found some potatoes that would stick down in the jar while creating a cork like seal at the top.


Every sweet potato has two ends, a stem end and a root end. You need to learn how to identify these ends because it is the root end that needs to be submerged. Sometimes a bit of root or bit of stem will still be attached to the potato, in which case, you have an easy job. Otherwise you need to look closely at the spud, the root end tends to be pointier, and the stem end chubbier.

You will need to make sure the root end stays submerged constantly for weeks until you see sprouts. My batch done with whole potatoes like this did not produce well.

2. Potato Chunks

The second method is to cut your potatoes up into chunks and put the cut sides down into water, I used a 9″ cake pan to hold these. Here it is less necessary to identify the stem and root ends, but this method required more frequent water monitoring.


Overall I had much better production this way. This way also had the benefit that once the sprouts came I could raise the water level, allowing roots to start forming at the base of the sprout, then a few weeks later, I was able to cut off the sprout, leaving some roots attached.

I also tried slices that wouldn’t fit into my cake pans suspended in a cup of water. Which also did okay.


Harvesting the Slips

Once the slips get a decent size, 4-6 inches, you cut them off and put them back into a water container so they can develop roots on their own. At this point, a humidity tent like a plastic bag would help since their main water source, the roots attached to the potato/chunk, has just been severed. However if you did as I did above with the chunks, raising the water level, each slip might already have roots.


Once the slips have a good quantity of roots you can transplant them out into your garden and they will make more sweet potatoes for you.

You can also harvest several rounds of slips from each potato chunk, after you harvest the first round the roots the potato grew are still working and it should quickly send up more slips. The process is still very slow though, overall for me it took close to 10 weeks from start to finish.

Late in the Fall, before frost, you can probably take cuttings from any sweet potato vines in your garden, and if you have a nice indoor setup you can probably store them indoors over the winter, and then plant them back out in Spring, saving you this step. I intend to try that this winter and I will let you know how it goes.

Greenstalk Review

April 22nd, 2016

As I’ve said frequently, one of the best parts of blogging is the free review swag. I sometimes turn things down, honestly, if I just think it’s a bad idea or I know I won’t like it. But I was happy to accept the Greenstalk container, because it looked like a good idea.

Essentially this is a strawberry pot on steroids. There are 3 and 5 tier sets and you stack them. It isn’t a self watering container, but there is an integral watering system whereby you put your hose into the top and it trickles down into reservoirs for each tier. These reservoirs could be bigger I think, in the sun in the heat of summer I think this could required multiple daily waterings.

Putting it together was easy, but it felt unsteady until I loaded it up with soil, and boy does this thing eat a lot of soil. So so so much soil. You will be buying a lot of potting mix to fill this up, but also your plants will have ample room for root growth. Most of the soil surface though is not open to the surface, so your plants will need to send their roots sideways into the middle of the structure. This middle however is away from the drip irrigation system and of course covered from direct watering so will likely be very dry, roots won’t want to enter it. I will have to check after the growing season is done but I’m not sure roots will get into the middle which makes it wasted space and wasted potting mix.

GreenStalk Planter

So, I have an in-ground garden I’m planting of course, but I’m also planting this thing. I actually planted in my garden weeks before I planted this. Guess which one has bigger plants? The Greenstalk does.

This is for a couple reasons, one is that I can’t water my garden, it is at the construction site where our house is being built and there is no plumbing or anything. So I have to rely on rain. I’m able to water the Greenstalk whenever as it is in the backyard of our rental. However, an underappreciated reason why the plants are doing better, and why they germinated faster, is because, this big columnar container, gets good sun exposure and the sun beating down on the sides heats up the soil, which heats up the seeds, which improves germination. This is good for now, in the Spring, but bad for Summer when that heat will increase watering needs.

So, if the proof is in the plants, the product works, everything I planted is doing great. Having the columnar design poses some planting challenges. You must either place it in the middle of a wide open area so there is decent sun exposure on all sides, or accept one side will be shadier than others and perhaps have that influence your planting decision. Option 3 is to MacGyver up an automatic turn table to slowly rotate it like a dish in the microwave.

Is this product perfect? No. It is still a fairly unstable structure, the tiers sort of clip together but it isn’t a strong connection, most of the structure is coming from gravity, from the weight of the soil. A couple of boys horseplaying around could knock it over, spilling plants and soil.

Filled up as it is, the thing is heavy, a caster base would be a big improvement so you could move it. I’m a big strong man and I can push it around, but many gardeners will not be able to. Especially if the soil is wet as it should be. And of course I need to push from the bottom tier lest I knock one of the top ones off.

Watering it is a bore, you hold your hose up to the top and stand there for a few minutes. A clip attached to the top tier that could hold a hose in a place would be an improvement. That way I could put the hose on and do some other chores while it fills up.

The top surface is wasted planting area, a top cap (smaller in diameter that would require separate watering) would be a good idea, to take advantage of the great sunlight the very top gets. you could put the aforementioned hose clip on this top piece.

So, what did I plant in this strawberry container on steroids? Not strawberries. I like strawberries in a garden where they can spread and fill a whole patch. The bottom tier is kale, the next two tiers are bush beans (I think bush beans will do very well in this thing, and so far I’m right), then it is basil, and the top tier is flat leaf parsley. I sorta did biggest to smallest from bottom to top, obviously to keep the upper plants from shading the lower plants too much. I think I’m going to really like this for bush beans, they’ll be easy to see, and easy to harvest. If the top cap planter existed I would put in a low water need trailing herb like thyme, or a low water need flower to bring in the pollinators like begonias.

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