Improve the soil in your vegetable garden by thinking about plant nutrition. Feed your vegetable plants in a relaxed way, the same way you feed yourself.

Provide a wide variety of nutrition to your plants to create a balanced diet. 

• Make compost with weeds and plants that have finished fruiting. If you layer lime and animal manures (chicken, sheep, cow, horse) amongst the plant matter in your compost bin you can also include your raw kitchen plant peelings and scraps without fear of visiting rodents. Once the compost has broken down, turn it to aerate it. (For this reason two compost bins are better than one. Keep one bin with compost ready to go onto the garden. As that bin empties, turn the newer bin of compost into it.)
• Plant your vegetables in a crop rotation to improve soil fertility (see Improve soil by crop rotation).
• Lay kelp seaweed around your fruiting plants and trees. The kelp will break down readily without your doing anything extra to it.
• Spread coffee grounds evenly around plants. This will improve nitrogen levels in the soil and deter slugs and snails. Develop a relationship with your local cafe owner to get regular supplies.
• Don’t waste leaf matter from your garden. When you pull up your spent pea, bean or broad bean plants, spread them under fruiting trees (photo, right). They will soon break down and help nitrogenise the soil. Rain will filter the goodness into the soil. Put lawn clippings in amongst the layers in your compost bin, or spread them around fruiting plants and trees. Do not allow the green clippings to rest against the plant stems as they may burn as they break down (see photo below left).
• Add organic matter to your trees and plants all year round. This will help mulch the soil to keep it moist. However, beware of building up too much dry matter around berries and grapes. Spores of mould and botrytis can stay in the organic matter and spread to the fruit in warm wet periods.
• Start a worm farm. Feed  plant matter to the worms and draw off the worm pee. Feed your vegies with 1 part pee to 4 parts water. Use the mix as a foliar feed on plants that are not near harvest. For plants near harvest, water at the roots. For plants that are stressed, use 1 part pee to 1 part water until the plant recovers.
• Make foliar feed for your vegetable and flower garden by soaking fish heads, seaweed or comfrey leaves in a large drum of water over a few months. Dilute the mix before applying to plants. Use similar ratios as for worm pee above. Continue to add water and fish, seaweed or comfrey to the drum as you use the feed.

Your fruiting plants will love you for the extra effort you make. You will be rewarded by heavier healthier crops.

Top, young mandarin tree fed with kelp and lawn clippings. Bottom, vegetable plants mulched to hold in moisture.

Click here for:

How to improve soil fertility by crop rotation

How to protect your vegetable plants from pests

Dig a new garden by the grid method

Build a garden bread oven

How to grow, train and prune table grapes

BUY A FUN RHYMING CHILDREN’S BOOK ABOUT MAKING COMPOST

‘Grandpoppa Poptop’s Compost Plot‘ - click here

Compost for kids

‘The basic knowledge this children’s book imparts about cycles of nature, nurturing our earth and growing our own food is invaluable.

Through its catchy rhyming story and funny pictures kids learn how Grandpoppa discovers the magic of compost on plants’ (Newspaper review, The Bay Chronicle, June 2011)

Buy this book by New Zealand author, Sue Hall at www.trademe.co.nz

My little girl loved this story from the first time, pointing at the pictures of funny Grandpoppa and his adventures with turning poo into compost. She laughed out loud, and asked for the story again, again! As a parent, I found this enjoyable to read to her … again and again’ (The Bay Chronicle).

Grandpoppa Poptop’s vegetables won’t grow well, no matter how much work he does. When the horse in the next paddock leaves him a present, he discovers how to make compost. He embarks on an amusing venture of discovery and collection on various parts of the farm and is eventually able to grow large, luscious plants.

(A selection of a few pages, obviously not including all rhymes)

Click here for:

How to improve soil fertility by adding nutrients 

How to improve soil fertility by crop rotation

How to protect your vegetable plants from pests

Dig a new garden by the grid method

Build a garden bread oven

How to grow, train and prune table grapes

Pests in a vegetable garden come in a variety of shapes and forms, from ladybirds, caterpillars, scale and aphids to rabbits, cats, pheasants and blackbirds. The best way to protect against sucking insects such as aphids is to practise crop rotation, thus not allowing the pest to establish itself in any one area of your garden. Sucking insects tend to attack plants that are unhealthy or stressed, so keeping your soil fertile and not allowing it to dry out too much or become too wet is also part of the battle. Strong healthy plants will resist an infestation, and, if attacked, will often grow through the problem. Provide the right environment for particular plants to give them their best chance: e.g. garlic cannot stand long dry spells and carrots do not like fresh fertiliser or prolonged wet conditions. Caterpillars on broccoli and cabbages can be crushed between the fingers (not a very pleasant job), or avoided altogether by planting the plants when the weather is cooler and butterflies have disappeared. Covering plants with a clear light mesh is also worthwhile. To protect against rabbits and cats I have built mesh fences around my vegetable plots (see photo below). Because there is plenty going on elsewhere in the section that keeps them entertained, the fences are enough to put them off getting into the veges.

Blackbirds tear up the soil around seedlings, especially if you have just watered them in dry weather or have dug in compost prior to planting. The birds are more interested in worms than in protecting your plants, so foil their digging with a chicken mesh circle around each plant. Chicken mesh is sold in 150mm wide coils. Cut off a length of 500mm and join it into a circle by folding the edges back into each other. Place the circle over a seedling and secure it with four small sticks (see photo below). I use the prunings from my grape vine, which easily last the whole year.

Young seedlings planted in rows are often uprooted by birds. Protect them by laying bamboo poles or sticks along each side of the row (see photo below). Leave them there until the plants are larger and the roots have established firmly. Then use them for your next planting.

Another usefull tool to protect plants from birds is to hang some old CDs on strings above the plants. As the CDs rotate in the breeze, rays of coloured light disturb the birds as they flash around the area.

Click here to learn how to improve soil fertility by crop rotation.

Add nutrients to improve soil fertility.

Grow, train and prune table grapes.

Build a garden bread oven.

Dig a new garden by the grid method.

BUY A FUN RHYMING CHILDREN’S BOOK ABOUT MAKING COMPOST

‘Grandpoppa Poptop’s Compost Plot‘ - click here

Grow great vegetable plants by practising crop rotation to improve soil fertility.

As the plants in your vegetable garden feed, they deplete nutrients in the soil. Some plants take more from the soil than others while some actually add nutrients. For these reasons it is important to practise crop rotation to maintain or improve soil fertility.

Don’t plant the same crop year after year in the same spot in the garden. Keep a balance by planting different crops in different places throughout the year.

Crop rotation will also help prevent a build-up of plant pests and disease.  If you can bear to do so, also leave some ground fallow (no plants in it) for a while. With added compost, this will allow the soil to build up its resources and cure itself of plant pests and disease.

Legumes such as peas and beans add nitrogen to the soil and are an important part of soil maintenance. However there is no need to have a science degree in order to understand how rotation works or to be successful at crop rotation.

You can choose to either divide your garden plot up into four quadrants with pathways or separate beds (three quadrants for crop rotation and the fourth to leave fallow) … or just keep a track in your mind of where you plant, and have planted, various crops. Rotate rows within your garden plots unless you plan to plant out a complete plot. The size of the crops you plant will determine where you place them.

Follow the general pattern below:

WINTER GREENS (e.g. broccoli, cabbage, Brussels sprouts, cauliflower, leek and kale) and SALAD PLANTS (e.g.lettuce, rocket, radiccio, sorrel, parsley)

followed by

ROOT CROPS (e.g. carrots, beetroot, turnips, parsnip, swede, potatoes)

followed by

PEAS, BEANS, ONIONS, TOMATOES, CELERY, CAPSICUM AND SPINACH (interspersed with salad plants – e.g. lettuce, rocket, basil, parsley, sorrel, radiccio, mustard)

and back to winter greens and salad plants.

…  but bear in mind that the period of time from planting to harvest varies amongst plants, and space will not always be available when you think you want it. Quick growing salad plants can be interspersed amongst almost anything.

Don’t worry if your pattern is not exact. Your plants will love you for trying and any rotation is better than none.

In the photo, the third bed lay fallow over winter, dressed with lime, general fertiliser, ash and compost. It is now being planted with courgettes and lettuces. In the second bed runner beans will be planted on the poles, where a broccoli crop has finished. The carrots and spinach in the front corner will be followed by capsicum (see photo at top). 

The bed in the distance will be planted completely over the spring and summer with continuing plantings of early, main crop and late peas to add nitrogen to the soil. The bed will then be dressed with compost, general fertiliser and mulch and left fallow over winter. The other three beds will be planted with winter crops as the summer crops are harvested.

Plant seedling crops alongside plants that are ready to be harvested (see the photo, right). Onions – between the bamboo protectors – have been planted next to silverbeet which is already being picked. The silverbeet will last a few more weeks. In the meantime the onions are protected by their leaves and are establishing early to ensure constant production.

Be careful during dry weather as the established plants will draw more water than the seedlings do. The seedlings will need to be watered separately.

I will cut up the roots of the silverbeet, once it is spent, rather than pull the whole plant out and disturb the onion seedlings.

Click here for:

How to improve soil fertility by adding nutrients

 How to protect your vegetable plants from pests

Dig a new garden by the grid method

Build a garden bread oven

How to grow, train and prune table grapes

BUY A FUN RHYMING CHILDREN’S BOOK ABOUT MAKING COMPOST

‘Grandpoppa Poptop’s Compost Plot‘ - click here

Rivets are designed to join two pieces of metal or plastic together through a pre-drilled hole. They can be used in making metal or plastic objects or for repairs around the house, such as re-attaching a loose piece of guttering or iron.  Rivets come in varied thicknesses and lengths and attached to a pin as shown. For general household use it is best to buy a selection of sizes. Once the rivet is passed through the pre-drilled hole, the head of the rivet remains on one side of the pieces being joined (see illustration below). On the other side, the pop-riveter compresses the soft alloy material of the rivet (usually aluminium) to create a flange that holds the two sheets together. Rivets can also be bought in steel, copper and nickel copper for specialist jobs where galvanic corrosion, electrolytic incompatibility or marine exposure might be a problem. (See also, What metal type should your fastener be?)

If you are joining plastic, it is a good idea to make allowances for a small washer on the back side of the join. This will stop the rivet pressing into the plastic while it is being attached, thus weakening the join.

How to choose a pop rivet size

Pop rivets are sold with a stated ‘grip range’, which is the total thickness of the parts being joined, so look on the packaging to assess the size of rivet you need for the job. For example, the length of a flat- or round-head aluminium rivet should be 1.5 times the diameter of the rivet shaft plus the thickness of the parts being joined.

How to use the riveter (rivet gun)

Align and temporarily clamp the two pieces of metal or plastic together in the desired position. Drill a hole (the same diameter as the shaft of the rivet) through both pieces of metal or plastic, in the desired place. You might need to punch a light dent in the metal first, in the exact place you want the hole (using a centre-punch, or even a nail), to make sure the drill bit does not skid as you begin to drill. (How to use a power drill) (Safety with power tools)

Once your rivet is selected and your hole drilled, look at your rivet gun. It has a selection of inserts attached to its frame. These can be unscrewed using a wrench that is usually also attached to the frame. The insert you need, for your particular job, will be the one that snuggly accommodates the pin of your rivet. Screw the correct insert into the head of the riveter.

Place the pin of the rivet into the head of the riveter as shown. Pass the rivet through the pre-drilled hole in the metal or plastic sheets. Check that everything is aligned and squeeze the handles of the rivet gun together until you hear a snapping sound. Sometimes this might take two or three squeezes. The rivet is now attached.

Usually the rivet pin remains in the rivet gun. Remove this by pushing it through with another rivet pin.

Rivets cannot be undone so it is very important to align the pieces being joined correctly.

To remove a rivet

Rivets can only be removed by destroying the rivet. There are two methods:

Drill out the core of the rivet. It’s not easy to determine the size of drill-bit needed just by looking at the rivet head, so drill it out with a smaller drill bit than you think necessary, then look into the hole to see if you need a wider bit to drill the remainder.

Another method is to grind off the head of the rivet and punch the core through.

This article will show you what is inside side winders on roller blinds and give you some hints on how to install or fix them.   
 

 Basically they work as cogs, activated by the links on the side-winder chain. When the chain is pulled, the chain’s links – which slot into cog grooves inside the side-winder – force the winder to turn. Depending on the configuration of the window, the blind can be rolled so the roller is exposed (as in photo right) or reverse rolled so the blind covers the roller. It can be set on brackets inside the window frame or above the frame. 
 

The blind fabric is rolled around a central metal tube. The top edge of the blind is attached to the rod by double sided tape (shown  to the left, in pink). The two parts of the winder are pushed into the rod at each end and then attached to the window frame on brackets.  Generally, the winding unit is made of four parts. The parts are joined together by a screw in the inner end (see hole in the end of the right-hand piece, photo below left). The next section is the casing for the bearing which allows the blind to revolve. The two left-hand parts form the bearing and the cog mechanism (see also, photo below right, which shows the cog raised for attaching the chain). 
The side-winder chain is joined into a loop which should hang down about three-quarters of the height of the blind (see window photo, extreme right). Thus the chain should be cut to a length of three-quarters the length of the blind drop multiplied by 2.  
 

Once the chain is wound around the cog it will be joined together by a clip (below right), BUT FIRST, it is important to position the chain length correctly. If the winder is to be on the left side of the blind, attach the chain, as shown below left, with a short length on the right-hand side. If the winder is to go on the right side of the blind, attach the chain with the short side on the left (that is, the short end should be at the back of the winder once it is in position on the window). Connect the parts of the winder together again with the inner screw. With the blind rolled around the inner tube, press the winder sections into each end of the tube. Connect the chain together by placing the end knobs of the chain into the clip holes (see below right) and close the hinge firmly. Attach the brackets to the window frame. Slot the roller into the brackets. Test the system. Most kits include a small clip that can be attached to the chain to stop the roller at the correct position as it is rolled up. 

You want to build a wood-fired oven with a cement mix that you can mould. You’ve seen instructions on how to build in brick and adobe but you’ve decided against using them because:

1. brick domes are too fiddly and difficult, and
2. adobe (clay and fibre mix) does not last in the weather.

You want to build a free-form oven that will last outside. This website shows you how to build a wood-fired refractory oven and how to make practical tools that allow you to use the oven.

Detailed instructions and photos include: Principles of construction (see below); Planning the design (see below); Materials needed (see below); Where to position the oven in the garden (click here, part 2); Building the base (click here, part 2); Building the oven floor — insulating layer and refractory layer (click here, part 3); Building the dome — refractory layer, insulating layer and chimney (click here, part 4); The plaster or finishing layer and decoration. The door. Curing the oven (click here, part 5); How to make your own wood-fired oven tools (click here, part 6); Lighting and using the oven (click here, part 7).

Principles of construction of a wood-fired oven

1. The inside diameter of your oven will depend on what you want to cook in it. An oven with a diameter of 750 mm will allow you to cook two 20-cm pizzas at a time (2 to 3 minutes each), or two chickens, or two trays of meat and or vegetables. If you wish to make larger pizzas, plan your oven with a wider diameter.
2. Wood-fired ovens are constructed with refractory material on the inner layer that holds the heat generated by the fire. Around this material there is a layer of insulating material that helps hold the heat in. On top of that is a plaster layer that protects the oven from the weather and allows for decoration if desired.
3. The chimney is placed at the front of the oven near the door. This allows for secondary heating of gases and keeps the heat swirling inside the oven before it makes its escape.
4. The height of the door opening should be 60–70% of the inside height of the dome. 5. A door, that closes off the oven opening, allows for roasting or baking.

Planning the oven

The bread oven shown in the photo above has an inside diameter and dome height of 750 mm (29.5 inches). The refractory layer is 100 mm (4 inches) and the insulating layer is 100 mm (4 inches) thick. The interior dome height is 375 mm (half the diameter of the floor) and the dor height and width are 370.5 mm (60 to 70% of dome height). If you wish to build an oven with a 1 metre-wide interior, increase the refractory and insulating layers to 120 mm; the door height to 60% of the interior dome height; and the door width to half the interior dome width. With a 1 m-wide interior, the oven base will have to be at least 1.24 m in diameter.

Preparing the plan

On a large piece of paper draw up the floor plan to true size. To create the circles, take a 1-metre length of string. Make a knot in one end through which to put a drawing pin or nail. Knot a small loop at 350 mm down the string and again at 450 mm and 550 mm. You can then put a felt-tip pen through the loops, hold the drawing pin at the centre of your page and describe the circles with the felt-tip pen. Once you have drawn the circles, draw in the door as shown above. This real-size plan will be very useful when you are deciding where to position the oven, and when you are building it.

Materials needed for a 750 mm-wide oven

120 kg of cement (3 X 40-kg bags)

20 kg bag of fire clay (buy this from potters’ supplies)

0.5 to 0.75 m plasterer’s sand

20 kg bag of hydrated lime

0.1 to 0.2 cubic metres of vermiculite

200 kg medium pumice (no bigger than 7 mm-sized pieces – 10 X 20-kg bags)

Water to mix.

Hints for building an oven with concrete

Always wear rubber gloves when handling concrete. The lime in the mix will burn your skin and dry out your nail cuticles. Mix it  in a wheelbarrow if you do not have a concrete mixer. Put the dry mix in first and blend well with a spade. Add the water (or wet lime mix) gradually to prevent the mix becoming too wet. Read the instructions for each section of the build to see how wet the mix should be.  Concrete takes two weeks to cure fully. You can build one layer on the next after drying over night. If you need to add another layer, leave the base layer rough, to allow for good adhesion. Moisten the drier base layer before adding the next. To begin building your oven, see Where to position your oven and Building the base.

This is part 2 of How to build a free-form bread oven.  Click here for  bread oven principles, plans and construction recipes (part 1), how to build the oven floor (part 3), how to build the bread-oven dome (part 4), the final layers (part 5), make your own oven tools (part 6) or cooking in a bread oven (part 7).  

Where to position a wood-fired oven in the garden

Face the door of the oven side-on to, or facing, the prevailing wind. Even if there is only a zephyr wind, it is better that any smoke that develops as you are lighting the oven blows away rather than into your face. Once the oven is hot there will be virtually no smoke, but it is better that any smoke coming from the chimney stack blows away from the cooks and the guests. Also beware of placing the oven close to a building with a sloping roof. If wind is likely to come down the roof line it may push smoke from the chimney back down the chimney or on to guests. If you have a bank in your garden where you could build the oven at waist height and stand on the ground below the bank to service it, you’re home laughing! You don’t have to build a base. But the retaining wall for the bank must be strong if you want your oven to be there a long time.

Building the base

The base of a wood-fired oven can be made from almost anything, but it must be sturdy because the structure of the oven itself is very heavy. Many people build the base from concrete building blocks. Others use a steel frame. I built the base for my oven with river stones. In the centre is an old concrete incinerator which gives vertical strength in the middle that the weight of the oven sits on. (A tower of building blocks in the centre could take the place of my incinerator.) The rocks in the round rock wall are held together with a mortar of 1 part cement to 3 parts sand. The wall must be built up gradually all round. I placed a full circle of rocks that fitted well and balanced well on their own before I applied the mortar. Once the rocks were balanced well I lifted each individually, applied mortar and then settled the rock into place. This took several days as I built only two layers at a time so that the weight of rocks did not distort the balance or mortar. As the walls rose, I filled any gaps between the rock wall and the central incinerator with scoria. On the top I laid a slab of concrete 750 mm (3 inches) thick, reinforced with steel reinforcing rods. The concrete mix was 1 part cement to 2 parts sand and 3 parts gravel. Use rubber gloves to protect your hands from cement burns. Leave the surface of the concrete rough so that the next layers will adhere readily.

What size should the base be?

The base must be at least the diameter of the oven plus the insulating layer and refractory layer. See the plan on page 1 here. Also allow more room in the front for the doorway. My base is more egg-shaped than round, by the time it reaches the concrete slab layer, to allow for the door tunnel slab. It was at this stage that the paper real-size plan came in very handy, rather than constantly struggling with a ruler or tape (see Planning the oven). The top of the completed concrete slab is about 800 mm above the ground.

Some people like to make the base a lot wider so that the base also forms a workbench alongside the oven. My preference was to keep the oven free-standing and the workbench a metre-or-so away because there is always more than one person wanting to have a go at the cooking. Also, the long handle of the paddle tool for putting items in and out of the oven needs a lot of arm room!

To learn how to Build the oven floor, click here.

This is part 3 of How to build a free-form bread oven. Click here for bread oven principles, plans and construction recipes (part 1), how to build a bread-oven base (part 2), how to build a bread-oven dome (part 4), the final layers (part 5), make your own oven tools (part 6), or cooking in the oven (part 7).

The insulating layer in the floor

The floor of a bread oven is made of two layers.

The bottom layer is made of insulating material that reflects the heat back into the refractory layer. It also prevents heat loss down into the base.

The top layer, just below the fire, is made of refractory material that stores heat.

Some people use empty wine or beer bottles within the insulating layer of the floor. The air pockets in the bottles provide insulation.

I made mine simply by using a 1 to 1 pumice and vermiculite mix. Both these materials are light and insulating. Mix the following to an oatmeal consistency.

5 parts vermiculite and pumice

1 part sand

1 part cement

ALWAYS MOISTEN A DRY LAYER BEFORE ADDING ANOTHER 

Spread the insulating mix over the moistened base slab to a thickness of at least 100 mm.  Take handfuls of the mix (using rubber garden gloves) and pack them around the edge to form a natural looking link between the floor and the rocks (see the darker wet mix to the right pf the picture).

Spread some aluminium foil over the base to within 5o mm of the outside edge of the base. Hold it in place with handfuls of mix around the edge.

Allow all this to dry over night. Cover the whole with plastic if you fear rain.

The refractory layer

The refractory mix is:

1 part cement

1 part fire clay

2 parts hydrated lime

9 parts sharp sand

Mix this carefully. It is essential that there are no lumps of lime within the mix. Mixing the lime to a paste beforehand is a good idea.

Spread the refractory mix over the floor to within 100 mm of the edge. (This 100 mm will later be filled by the dome’s insulating layer.) You could make the whole floor layer with this mix to a depth of 100 mm.  Make it level and smooth it off with a trowel, because this will be the working floor you slide your food onto. Before it dries, mark on the outline of the circles of the inner dome layer using the real-size plan or the knotted string. Etch a criss-cross, rough pattern into this area. With handfuls of the refractory mix build a low wall around this circle. Leave the surface rough (as in the photo below). This is the beginning of the dome wall. Leave it to dry before building the dome.

I chose to use fire slabs for the floor. They are laid on top of a wet 50 mm refractory mix layer. I used 10 fire slabs, 270 mm x 270 mm x 40 mm as in the design below left. I drew the floor plan onto the slabs once they were laid. Then I held the slabs more securely with a ring of refractory material (i.e. the first layer of the inner layer of the dome), still leaving 100 mm around the edge for the insulating layer.

Leave all this to dry over night.

To Build the dome, click here.

This is part 4 of Building a free-form bread oven. See here for bread oven principles, plans and construction recipes (part 1), how to build a bread-oven base (part 2), how to build the oven floor (part 3)), how to build the final layers (part 5), make your own oven tools (part 6) or cooking in a bread oven (part 7).

The dome of the bread oven is constructed by building over a wet sand mould. The sand is held in place and formed in a perfect dome by making a 3-D pattern out of corrugated cardboard.

Cut out two semicircles of corrugated cardboard at the same diameter as the inner dome, i.e. 750 mm (see the plan in part 1). Cut one from the centre top straight down to half way. Cut the other from the centre bottom to half way up. Lock the two together as shown in the photo below left. Place them on the oven floor in the same position as shown in the photo.

Mark the position of the door on the cardboard and cut vertically as shown left. Also cut a model of the hole of the door opening (as in the plan in part 1 and as shown below right). Pack the door shape against the dome cardboard, using wet sand as shown below right. This gives you a model for the shape of the inside of the door tunnel.

Pack wet sand in all quadrants until you have a smooth dome of sand that allows only the top edges of the cardboard former to show. Pack wet sand in a tunnel shape from the door hole forward and up to a piece of hardboard stood vertically on the front edge of the circles you have marked on the floor slab (below left). I cut the piece of wood to the door shape as a guide to keep the tunnel even and so I could see the door shape as I built the concrete layers of the dome. A large tin can provides the mould for the chimney hole. Build the sand into a mound on each side of the chimney as shown on the photo below left. This will form a slot that will help direct the smoke up the chimney. You will have to build the refractory layer on top of this sand mould in the same day, before the sand dries out and collapses.

The refractory layer

The refractory layer (above right) is built handful by handful, layer by layer until it completely covers the dome.  Plan to leave a gap of 100 mm between the refractory layer and the hardboard. This will be filled with insulating mix (the darker mix in the photo, above right) to prevent the front of the oven becoming too hot to work against.

The refractory mix (see here for the recipe) must be mixed with water to a firm consistency. If the mix is too wet, the weight of the upper layers will bulge the lower layers out as you build.

As you mould a handful,check that any lime powder is mixed in well. Estimate that the handful is 100 mm thick. Place it next to the last handful and blend the two in together with your fingers. As you approach the top, place a 100-mm handful on the top. This will help you judge the thickness of the layer as you build over the top of the dome.

Fill the 100 mm gap in the front of the oven with insulating mix (see here for the recipe).

Gently wiggle the tin can and remove it before the mix dries.

Allow all to dry over night.

I used a ceramic field tile for the centre of my chimney, placed it on the dry refractory layer and built it in with the insulating layer (see photos 2 below).  However, if I were to build again I would make the chimney out of refractory mix, at this stage, by building it up around a corrugated cardboard tube placed inside the hole in the refractory layer of the dome while it was still wet.

If you intend to place a metal chimney above the refractory one, make sure the top circle of the refractory chimney is level and smooth to accommmodate the metal. Keep the outside walls of the chimney rough so that the refractory mix will stick to it well. 

Leave the refractory layer overnight and for most of the next day to set. Then remove the sand and soggy cardboard from inside. Do not remove the cardboard from inside the chimney at this stage. Now you start feeling as if you’re really making an oven!

The insulating layer

If you have not already built your chimney as above, place a ceramic field tile above the chimney hole and hold it in place with a small amount of refractory mix. Cover the dome with aluminium foil and hold it in place with chicken mesh.

If you are using a field tile as the chimney attach some chicken mesh around it to allow the refractory mix to adhere. If you have made the chimney yourself, you will simply cover it with insulating mix after you cover the dome. 

Mix some insulating mix to an oatmeal consistency (see the loose handful in the photo, above right). When applied to the dome, it will pat into a more solid, firm form. Work consistently round the dome as you did previously with the refractory layer (see below left). Build up the oven door hole to another 100mm above the first layer (below left). Place a nob, 100-mm thick, on the top of the dome as a template and build up the walls to meet the top nob (see below left). Attach a metal chimney vertically above the chimney and hold in place with refractory mix.

See here to apply decoration and the final plaster layer.