Building a small production greenhouse

When we rebuilt the house one thing we decided to add was a small greenhouse. We picked a spot with great sun exposure and a convenient pre-existing wall and built a small glass and granite building. The same architect that designed the house remodel gave it some nice touches too.

We added a metal table with automatic watering above it on the taller side, which is where we do most of our reproduction work and left the smaller side for mostly potted plants. In the middle we built a wood walkway between the two doors.

The last change we've done is to add some benches to the smaller side and extend the watering system to that side as well.

We've been extremely successful at doing all sorts of reproductions using this greenhouse. For example we start all our tomatoes from seed we collect from the previous year's production (that's only possible because we use heirloom varieties from the The Real Seed Catalogue and not the usual hybrids).

Last season we had a tomato plant grow out of the ground by chance. We let it ride and it fruited well past the normal season (we ate the last tomatoes in January). After that much success we decided to start planting some tomato plants on the greenhouse ground to get a small but out-of-season crop. We used the low side of the greenhouse and added a watering line on the ground as tomato plants supposedly don't like to be watered from above. That also went well but it was always a small crop. That eventually made us want a much bigger greenhouse to have much more actual production instead of nursery...

After shopping around quite a bit we found a local supplier that would build a 14 by 4 meter poly tunnel for a very reasonable price. We decided to set it on the edge of our forest garden in a spot with good sun exposure and that also helped with bringing some immediate wind cover to a somewhat exposed part of the field. The construction was all done in a single day last summer. The builders brought most of the structure pre-built with them and the day's work was mostly assembly. It started early in the morning with the setting of the posts. This was done extremely quickly with a gasoline powered drill. They were pre-prepared metal posts with a cylindrical concrete base that was buried for stability.

After all the posts were level and straight the pre-bent arches where slid into place and bolted on.

Once that was done they dug two trenches on either side of the structure. This was done by hand and was by far the most grueling part of the job, especially since the sun was high and hot by then.

Once that was done they unwrapped the main length of plastic and stretched it on top of the structure.

After the plastic was over the structure they stretched it firmly and held it in place by placing it in the two ditches simultaneously and filling them back up with the soil that had been taken out and pressing it in stepping on it. Once it was stretched they bolted it to the end arches. The next step was to assemble the frames for the doors on both sides. We opted for a single door on one side and a double one on the other so we could fit the electric buggy in if we wanted to.

Both the single and double doors have a window above it that can be closed or held in place in one of two positions. Here the winter position is shown, giving some ventilation but not facilitating the egress of hot air. The summer position is swung the other way round so the hot air rising is naturally driven out. All the doors and windows have rounded corners but are set into square frames. This leaves enough of a gap that even if everything is closed (for the coldest part of winter) there is a decent amount of ventilation.

After the build was complete we drove the electric buggy through the double doors bringing a very large amount of compost from our large piles. After spreading it evenly we planted the first crop, using cardboard to create walking paths in the middle and sides.

The cardboard worked well at controlling weeds but started to waste away relatively quickly so we used some weed barrier fabric to cover the paths instead.

To water the greenhouse we started out with a simple square lawn sprinkler driven by a water timer. This worked fine in the beginning but once the plants started growing the sprinkler would often get covered by plants and not water everything evenly. We've now installed a new overhead system. We'll do a separate post detailing that.

We've been having great success with all sorts of vegetables so far. The first tomato plants have just been added and we'll see how that goes. This is not just for annual crops though. There is a selection of tropical plants in pots about to be put in. The selection includes banana, annona, papaya, mango and a few other smaller stuff. The banana may be pretty marginal but we think we have a shot at getting a crop from most of these even if it's not every year. And that's even before exploring some of the passive heating options out there (long but very interesting video).

Building a practical large compost pile

We have two donkeys continuously outputting large amounts of manure. Between leftover straw and manure we add about 3 cubic meters per month to the compost pile. Initially we had been piling it on the ground but it's hard to build a large enough pile to generate enough heat for proper composting. Since the farm is on a slope and each field a terrace with a drop to the next field we decided to build large vertical manure piles on the field just below the donkeys. That way it's easy to drop in the fresh manure from the top and then empty the finished compost from the bottom. We decided to build three piles side by side so we could have at all times one being filled, one composting and one being emptied.

We started by leveling the ground a bit and then opening four large holes in the ground where our pillars are going to go.

We had some leftover granite pillars from dismantling old vine pergolas that we carried over and tilted into each of the holes.

Some careful maneuvering and an old industrial drill bit got the pillars positioned vertically.

Once they were vertical we carefully nudged them into alignment and then filled in the holes to keep them in place.

With the four pillars in place we set out to build the base. We bought some concrete blocks and used some left over granite rocks.

We used the granite blocks to build a solid base to hold the pillars and the four concrete block walls.

The four walls went up relatively quickly. To secure the pillars properly we connected some metal cable between the pillars and the back wall so they have nowhere to go.

We built all the walls with some spacings between the blocks for added ventilation to improve composting.

At this point we had the basic structure done and only the front wall missing. We had sized the whole construction so we could fit 3 standard pallets as the face of each pile. They allow for great ventilation and are cheap and easy to replace. We attached L brackets to each pillar to create mounting points for the pallets. A metal wire connecting all the tops of the pillars increased the structural stability and gave us a nice place to attach the pallets to. The top one we just fixed in place with some wire on the top and screws through the L brackets on the bottom.

That left a large enough opening to get the compost out. For the bottom two pallets we made them easily removable. We screwed in some tabs on the bottom of the top and middle pallets to hold the middle and bottom ones in place. The tabs on the back of the pallet are just fixed in place but the front ones pivot on a single large central screw so they can be rotated to be able to remove the pallet. The bottom of the middle pallet is held in place by a pin going through the pallet and through the L bracket and the bottom pallet with a pin inserted into a hole in the base.

It takes us about 4 months to fill each of them. This means they're just about the right size to cover the whole load of a year. We usually put some small branches once in a while to create space inside them and then just drop in manure and straw. 

After they are full it takes around 6 months to compost. That leaves us 2 months to empty it before we need to reuse it.

We use the electric car to load up compost from here and then drop it wherever we need it with the electric tipping bed. We never use the compost below the top of the granite base so there's always a compost base to make the process start faster. The back of the piles are also against the granite wall of the field above which has quite a few openings. Worms have already fully populated the piles all by themselves so the composting goes pretty quickly.

Egg yolk pudding

All sorts of things are named pudding, sweet or savoury, with ingredients that can include dairy, starch, rice...

In Portugal puddings are desserts, cooked in specific pleated moulds with a lid. Milk-based puddings are common, and typically go by "french pudding". But if you want a heavenly pudding, all you need is egg yolks, sugar, water and some Port wine. It is easy to make if you are strict with some details. 

The first thing to do is coat the mould with caramel. Of course there is ready made caramel, but it is fairly simple to make it directly in the mould, burning the sugar on the stove (avoid this if your mould has any soldered parts). You can also cook it aside in a regular pan and then pour it into the mould. 

  • 130 g sugar for the caramel (approximately, use more if you cook it in a pan, there will be some caramel left)

Caramel is very easy to make: just put the white sugar in the pan (no water) on medium heat, and it will quickly begin to turn into a thick brown paste; stir gently, there will be some smoke and a caramel scent. Be very careful, sugar boils at 186º Celsius (367º F) and getting a caramel burn is not nice. As soon as you stop seeing any white sugar, get it away from the fire and handle it quickly, because it turns solid very fast as the temperature goes down. Roll it around with the help of a spoon, until the inside of the mould is all coated. If you cook it in a pan, pour it in the pudding mould and use a spoon to quickly coat the mould, middle axis included.

By the way, the caramel in the first picture has been cooked on the fireplace (not recommended!) because our induction stove would not work on the aluminium mould. In this case, the safe way to go would have been to make the caramel in a pan...

Warning: do not let small children near you as you prepare caramel - the sugar burns, there is smoke, and everything has to be done quickly. You will not be able to supervise them and caramel burns will be harder to avoid.

When the mould is all coated, leave it to cool while you prepare the pudding. We leave it upside down on a plate. In case too much caramel has gone into the coating, it will drip. You can remove the excess caramel over the rim of the mould when it solidifies, just break it off with the help of a knife. It will be very brittle and not as sweet as caramel candy, but ok to eat.

Now for the pudding dough. 

First of all, weigh the 4 ingredients:

  • 800 g sugar
  • 275 g water
  • 400 g egg yolk (approximately 2 dozen eggs, preferably at room temperature)
  • 80 g red Port wine (a tawny works best because it has a more intense flavour and is also much cheaper)
If you have a good scale you can do the weighing directly on the pan: weigh the sugar first, zero the scale, pour in the water. 

Take your sugar to a gentle boil and test for the "sugar point" as we say in Portuguese, which is actually the density of the sugar+water mix or the sugar sirup stage.

We want the "pearl" point, which is easily detected if you take part of the mixture on your spoon, blow a bit to cool it down and then let it drip slowly from the spoon. The sugar will flow and then stop, leaving a little pearl attached to the spoon. This is the density you want, turn off the heat and let the sugar cool for a while. The amount of water and sugar indicated should bring it pretty close to the desired density as soon as it boils.

In the meantime, use the scale again and weigh the yolks and the Port wine. We used separated yolks sold in 1 kg cartons. You will get the same with 2 dozen large eggs, separating the yolks carefully. This will be a good task for children to help, and you can use egg-separator gadgets...

Measure the Port, this small amount is enough, so a bottle will last many puddings.

 Stir gently (do not whisk, just loosen the yolks a bit with the wine).

By the time the sugar sirup has cooled down, pour it slowly into the yolks. It is easier with two people, but you can do it easily with a saucepan. Start with just a drip of sugar sirup, stir the yolks to mix it in and continue, making sugar drip faster as the mix warms up.

Now pour the dough into the caramelised pan. Put the mould into a pan where it fits (not too tightly) and put the lid on. The pan should have some water, but not too much; as you sink the mould, the water should not go above more than half its height.

Put the lid on the pan as well and turn the heat on. As soon as the water boils, bring the heat down to a steady slow boil point. Let it cook for 1 hour. When the time is up, turn off the heat, take the pudding mould out of the pan (be careful with the hot water) and take the lid off. The top of the pudding should look well cooked and the overall feel should be jelly-like, not liquid.

It will probably smell wonderfully, but you will have to wait at least 12 hours to remove it from the mould and look at the result. If you make the pudding in advance (up to 1 week), you can just let it stay in the mould until just before serving - it will look better and there will be no danger of it collapsing.

The pudding is an excellent dessert to bring if friends invite you over for dinner. Just carry the pudding still in the mould, unmould it in the destination to a local plate, and take the mould back on the same plain bag (lid on).

The result, we can assure, is amazing.


Converting Par36 bulbs to LED

Last year we got an electric car to go around the farm. It's a Toro Workman and it has an electric tipping bed that carries 400kg and climbs our steep paths with ease. We're really happy with it. We bought it used and the company that sold it was less than stellar in getting it to us in good condition. One of the things we had to fix was a broken head lamp. The lamps are Par36 28V bulbs, so the whole headlamp is actually a bulb. One of the two was fried and since the two are wired in series this meant we didn't have any lights. This sucks in nice winter days when the temperature is fine but the day ends very early.

It was getting late and the cat wanted a ride. We couldn't do it without lights though...

We had asked the local glass supplier to cut out the back of the bulbs. He did a decent job even though he didn't center his drill very well. This meant the cut wasn't parallel to the bulb orientation.

We got some pre-packaged LEDs off ebay. They were a nice round shape that would fit nicely on the back of the bulb. Now we just needed to secure them properly and wire them up.

We took a piece of leftover IKEA board that we didn't use and cut out a square with a round hole in the middle.

We used a hammer and a nail to open up two small holes in the board to fit the two pins from the LEDs.

We also took some leftover power cord and made two extensions.

Then it was a matter of putting the board in and soldering the two extensions to it. We used some pieces of heat-shrink tubing to protect the soldering and avoid short-circuits.

To secure the LEDs to the board we used a nylon screw on the opposite side of the soldering. We tried gluing it on with a bunch of things and it didn't work. We glued on a few pieces of wood/board to level the boards against the two cut bulbs, to solve the problem with the cuts not being centered. We then trimmed the boards to size (right one was trimmed after painting). To make the board cleaner we masked the LEDs themselves and painted the boards with a gray spray can. 

To attach the boards to the bulbs we simply used duct tape. We were careful to make sure the tape reached the edge of the bulb, as that's what is then put inside a rubber piece and put into the car so the tape becomes mechanically locked. It taped on just fine though.

Here are the two bulbs finished.

Here is one bulb put into its rubber sleeve, ready to install into the front of the car.

And here is the end-result in the car. The cat was gone by then though so no ride for him.

You may notice the right bulb is brighter than the left. That's because initially we wired the two in series. The LED's we got were rated 11-28V but since they have buck converters to achieve that you can't really wire them in series. Instead we added a DC regulator to get 12V out of the batteries 48V and then ran the two bulbs in parallel. It now works great, with much less power consumption than the previous bulbs, which is relevant in an electric car.

Building an observation hive

When we started beekeeping one thing we read in multiple places was that getting an observation hive was a great way to learn. An observation hive is basically a glass sided bee hive so that you can look into it without putting on a bee suit and disturbing the bees. 

Michael Bush has a great page on what to consider in observation hive design. We used that page and some advice from the beesource forums to design a single wide 6 frame hive. We did an initial sketch in Google Sketchup:

After thinking it over and detailing the design we defined all the wood sizes we needed and had them cut for us. We also ordered two framed glass panes from a picture frame supplier. With all the supplies ready we got to work. We build the two sides, one with a hole in the middle that will serve as the bee entrance:

We quickly built the basic frame, using some right angle metal pieces for strength and two threaded rods at even spacing to attach the frame supports and to make sure the top bar was straight.

This was our first test fit of everything.

Two lengthwise pieces on top and bottom will seal the gap against the glass frames.

We also opened up the entrance side hole to 31mm and fitted a brass hose connector so we can then attach a hose to connect the hive to the outside. We had to use an adjustable drill bit as we couldn't find a 31mm or 32mm bit. These things suck for this job. The hole was already cut at a smaller size so the center part of the bit that guides the hole had nothing to connect to and since the drill only cuts on one side it becomes unstable. Because the bit is so long it swiveled pretty easily even when using a drill press. Only after getting the initial depth done did the drill stabilize as it became locked into its own hole. Next time we need to plan ahead more and use the adjustable drill for the initial hole and them finish the inside with the smaller bit.

A first test fit with everything in place. We made some frame supports with folded sheet metal held in place between two bolts and two washers on the threaded rods. On the right and left sides the frame supports are also folded metal and screwed in directly to the wood. We're still considering making these a bit better. They only have a stop for the frames in the back so the frames can still fall forward.

The glass frames were attached with some simple metal holds on top on both sides, and three nails on the bottom plank to make sure the glass frame fits snuggly (it's not nailed in).

Here's the final assembly. Note the cork top in the middle of the top bar. We drilled 19mm holes aligned with the center of each of the top frames. That way it's easy to open/close them for adjusting ventilation or to setup a rapid feeder.

After getting the finishing touches done we'll be putting it in a small building on the farm and routing a one inch transparent hose from the entrance through the wall of the building so the bees can get in and out freely without being able to enter the building itself. We'll probably do a spring split into the observation hive to be able to observe the bees make a new queen.

Early spring recipes: purple cabbage and chicken stew

This is what we call comfort food. It is lovely for an early spring dinner by the fireplace when it's cold outside. Serves 5-7.


  • 2 medium sized onions
  • olive oil
  • 1 purple cabbage
  • 6 boneless chicken breasts, sliced in cubes
  • 1 table spoon Dijon mustard
  • 1 cup white wine vinegar
  • salt
  • bread or toasts

Fry the onion in olive oil until golden, add the chicken and stir until the outside gets cooked. Slice the cabbage in quarters lengthwise and remove the thick white part. Slice into small bits and add to the pot. Stir until the cabbage softens a bit and then add the mustard, vinegar, salt and water. How much water you add depends on how much you like dipping bread into the stew. If you don't - add just enough water to cover half the height of the cabbage and chicken in the pot. If you're using a pressure cooker, close the lid and cook for 15-20 minutes after it reaches steam. In a regular pot count on 45 minutes to one hour.

Serve with toasts or good quality bread.


Adding comb guides to regular bee hive frames to go foundationless

We've been running foundationless frames on all our hives. It's less work and may have some health benefits for the bees. To do this though we've had to retrofit comb guides to our regular bought frames. We don't make our own equipment. Our hive supplier is cheap enough and we're small enough that it wouldn't make sense to start making them, so we have to modify them to our needs.

We started by using tongue depressors to press into the groove carved on the inside of the top bar of the frame that would normally fit the wax sheet. We found that two of them fit snugly into the frames and initially just pressed them in by hand and started using them. What we found was that even after the bees had put propolis on the depressors they would still sometimes fall out of the frame, probably once the hive got hot and the wood expanded. We had a hive lose a full comb probably as a combination of wood expansion and the comb's weight. Our method for these is now to put in a small amount of regular wood glue into the groove and then press the tongue depressors in. This seems to work fine and we haven't had one fail yet.

Our next issue was that sometimes the bees would actually build comb on both sides of the tongue depressors, so two combs to a frame, instead of using it as a guide. We had this happen with a new swarm. Once they get into that rhythm it's hard to break them off of it as they'll base the location of the next comb on the distance from the previous one, again ignoring the guide on the frame. We've recently tried a different approach which was to glue and nail a wedge to the full length of the frame. We had a woodshop take a 2cm by 2cm section length of pine wood and cut it in half lengthwise between opposite corners. This gave us the triangular section wedge to glue onto the frame. We cut it into several pieces with the length of the internal frame width and glued it on with wood glue and then nailed it in. The nailing was the hardest part, and a nail or staple gun might be ideal for this. So far we've only done a 10 frame box to test this in one of this year's swarm boxes.

The end result are two types of foundationless frame that we use in our swarm traps

When the bees take the hint and follow the guide the end result is nicely drawn pristine white wax.

The tomato season is on!

Winter always seems too long and in January we have all those seeds patiently saved from the previous season, plus the packets with the new things we want to try, and little patience to wait for warmer days. In previous years we have sown our first tomatoes around January 20, but sometimes those early trays take so long to germinate that the seedlings are weak and easily surpassed by the ones sown a month later. 

This year, however, we had such a cold, rainy winter that we did not even consider starting anything in January. But as February went by with one rainy day after the other we counted the days and worried about all the work that was being postponed: soil preparation (impossible to do with soaked soil), sowing, transplanting. By February 15 we made a trial with our most robust tomato seed, and on the 22th we took the chance to prepare some trays and try to start the first sample of our favourite and also some new acquisitions. 

There are two ways we sow tomatoes: using old styrofoam trays (they are put away at the fishmongers) or the regular sowing trays. In any case we fill them with a germination substrate we buy at our vegetables nursery. If we use our regular soil it is so full of seeds we get all kinds of weeds germinated well before the tomatoes! 

So the first step is to fill the trays: the substrate comes dehydrated and compact, we have to loosen and hydrate it. After that it is easy to fill the trays and compress the soil in each cell.

Just to be sure we gave most of our favourite varieties a try, we prepared two 8x5 trays. We chose 8 of our tried-and-true varieties and also picked some seeds from the 8 new varieties we have ordered this year. For weekend gardeners, it is really insane to test for 8 new varieties in the same season, but as we go through all the wonders in the Real Seeds website, it becomes very hard to resist...

It is easy to get all the seeds mixed up, so we always prepare the labels and label the rows in the trays prior to laying the seeds. In this case, we used tongue depressors (also used for beekeeping tasks) cut in 4. The little white plastic labels are nice and easy to reuse but we buy a bag and they are soon spent. We need larger packs.

When each cell has its seed, it is time to slightly bury them (we learned the layer of soil on the seed should be approximately twice the size of the seed). Now there is a problem with seeds in the greenhouse: mice are hungry this time of the year and they like seeds. So some times we wait, nothing sprouts and we see that the seed is no longer there. Not so common with tomatoes, but almost certain with pumpkins, melons and watermelons: their favourite! So we already have some hardware cloth folded to the size of the trays. They can be left until the seedlings are 2-3cm high and there is no seed any more. By that time we have to be careful with snails, but we will talk about them later.

Now it's time to select a good spot on the greenhouse table, check the irrigation timer, and hope the next weeks will bring some sunny days. The greenhouse is not heated, but keeping the door shut and taking advantage of the longer days we have now, our average temperature in the past weeks has been 12.5º C, with 10º C minimum. Tomato seeds would appreciate some 5º extra, let´s see how they will do.

It has been a week since we made this sowing, no seedlings have sprout yet. But we expect to have some next weekend. As we have lots of seed from last year, we have put some in a pot a week prior to these. It has 2 weeks now, and a regular hair of good looking seedlings. 

So we are optimistic about our first batch of 16-variety tomato seeds.

We need these tomato plants to develop and leave rooms for all the other vegetables and flowers we will start in the greenhouse. We are just beginning the season and the table is already well stocked: besides the two tomato trays, there are two large styrofoam trays with our most common varieties: the large oxheart which are cherished in the neighbourhood and the heavy-production plum tomato we use for preserving and making sauce. Another tray is starting our first parsley. Two trays have echinaceas sown in autumn: they overwintered in the greenhouse, died back and are now sprouting. Hopefully in two or three weeks the weather will be warm and we will be able to take our seedlings outside, start new batches and get room for basil, zinnias, scarlet sage, ...

Attracting swarms to get free bees

We have told the story before about how we stumbled into beekeeping. Our first year as beekeepers we were able to attract a swarm directly into a hive without much effort. Last season we got 4 the same way (although one entered the owl box) and even caught one on video. So this year we have our method pretty much figured out and are hoping last year wasn't a fluke. Here's what we do.

We start by getting a normal hive ready. We use all medium sized frames and boxes. We use all foundationless frames to let our bees build their own wax. Our swarm traps are really a full hive setup, with a base board, a box, 10 frames, and inner and outer covers. We tend to look for hives that have already been used by the bees. This year we have a couple of boxes we removed from the hives to consolidate them for winter that should work better for swarm attraction.

After we setup the hive we then take a small ziplock bag and stuff a paper towel inside and then wet the paper with lemongrass oil. We then close the ziplock almost all the way leaving a small entrance for the smell to get out slowly. That bag gets dropped to the bottom of the hive. We also drop a couple of drops of lemongrass oil on the flying board to help attract swarm scouts looking for locations to test out. You can replace the lemongrass with a number of industrial attractants although we've never tried them.

Once we have the hive fully assembled and with the lemongrass attractant deployed we set it somewhere where it's not in the way and make sure the hive is level. That's particularly important as we're using foundationless frames. Bees will follow gravity and build their wax hanging down vertically. If the hive wasn't level the combs wouldn't be aligned with the frames. So far we've set out 4 hives in a few spots. We've doubled down on the wooded area where last year we caught two large swarms. We're now completely out of hives and thinking of how many we want to order from our typical supplier.

Our main idea is to set out full hives that we can then just move into the bee yard without any other intervention. Moving them once they are full is a little harder than if we were using a lighter box but we've managed fine so far. If you want to look into this in more detail there was a pretty large study done on what characteristics will attract swarms. The main outcome of the study is the following list of characteristics of the optimum swarm trap:

  • Set 5 meters off the ground in a well shaded but visible area (distance from the parent hive doesn't matter)
  • An entrance that's about 10-15 square centimeters large at the bottom of the box and ideally facing south (shape is irrelevant)
  • A box that's about 40 liters in volume (both deeps and mediums should be fine, the study only really tested 10, 40 and 100) and also airtight and dry
  • The smell of wax and lemongrass or other attractants. A frame of old black brood comb is often recommended here.

Spring is upon us and the bees are flying

We had the first few early spring days at the farm. All the early bloomers are in full force and birds are everywhere.

The bees were in full force as well taking advantage of all the early flowering going on. In our climate bees never really stop but you can really tell that their activity has slowed down when it gets colder. The experience from the two seasons though is that August is actually much more of a worry because there's nothing to eat. We really need to find some plants or trees we can add to the farm and possibly irrigate to get over that period more gracefully.

At this point though they seem to be in great shape. 

All 6 hives had activity with one of last year's swarms clearly booming.