Making leaf castings in hypertufa is quite a popular project. I get many questions about the ins-and-outs of how to make them. This tutorial will guide you successfully through the steps and I am sure you'll be on your way to adding one (or more) of these beautiful garden art objects.
And I must mention ... remember to practice safety first! You're dealing with portland cement, which is caustic. Wear your gloves; wear your goggles; and wear your face mask. For complete information on all you need to know about working with hypertufa safely, please refer to Chapter Five in "The Hypertufa How-To Manual".
Also, leaf casting can be a bit tricky. Getting the hang of finishing the edges, for instance, may take a bit of trial and error to become successful. You do want to taper off the 'tufa as you get to the leaf's edge, but not so thin that a part will crack off, either during the cure or on-up-the-road.
Remember: practice makes perfect. Start with smaller leaves, then progress to bigger ones.
I also recommend you use some sort of fortifier in your recipe. Refer to "The Hypertufa How-To Manual" for more recipe information.
Or, please visit: www.HypertufaBooks.com
So that you are aware, but not to discourage you in any way from doing this project, you cannot make finely detailed castings of leaves with hypertufa. The nature of the 'tufa recipe ingredients does not make a super smooth mixture.
Finely detailed leaves require a very smooth consistency concrete recipe. For information on casting leaves with concrete, please refer to the following information found on my website:
Concrete Leaf Casting Techniques & Super Tips For Success
http://www.The-Artistic-Garden.com/leaf-casting-super-tips.html
MATERIALS NEEDED
Gunnera leaf
Rhubarb leaf Many leaves wilt quickly, so don't harvest it until you have everything mixed up and ready to go; or keep your leaf in a bucket of water until you're ready. Cut the stem off at the base of the leaf.
Some ideas for leaves to use for this project:
Small leaves: Oak, Maple, Hosta
Large leaves: Rhubarb, Giant Hosta, Canna, Ligularia,
1 large bag of sand (any kind will do)
As an example, a rhubarb leaf will need a 40-lb. bag
Your favorite hypertufa recipe
For stronger leaves and/or larger leaves: use an admix recipe; you may also want to use drywall joint tape in addition to admix recipe; for a large size leaf (like a rhubarb) you will more than likely use almost an entire 40-pound bag of portland cement -- gauge your other ingredients accordingly.
Optional: chicken wire, drywall joint tape or hardware cloth for extra strength of the finished leaf
Water
Plastic wrap
Paint or stain (optional)
1. Important: to get the finest visible veining details possible for your leaf, you must FINELY pulverize the peat moss. Chucks of peat moss in your recipe are NOT recommended for this particular project.
2. Make a sand pile to support the leaf. There needs to be enough for the leaf to rest on, plus a couple of inches extending around the edge. Smooth the sand into a mound. The higher you mound the sand, the more arch your finished leaf will have. The sand pile/mound will support your 'tufa covered leaf and create the amount of curve and shape that you desire.
3. MIST the sand mound with enough water so that it will stay together. You want to be able to maintain the shape of the mound over the next few days.
4. You may have to make a couple of attempts to mound the sand to really support the various undulations that a natural leaf has. Make sure the leaf is supported in the "shape" you want your hypertufa leaf to be. Hypertufa is HEAVY when wet and is most definitely going to make any un-supported part of the natural leaf sag. Take your time to get the sand mound exactly as you'd like your 'tufa leaf to be shaped.
5. Cover the entire mound and surrounding edge with the plastic wrap.6. Lay the leaf face down on top of the plastic wrap. Make sure it extends a couple of inches past the leaf edges.
7. Optional step: apply a release agent to the back side of the leaf (the side that is now facing you). Many people say Vaseline is the best. Do not use a cooking oil spray like Pam. It doesn't work well.
Note: for more information on release agents, please refer to Chapter Ten in "The Hypertufa How-To Manual".8. Mix your hypertufa recipe. For this project, get it to about the consistency of peanut butter, or very thick cake batter. You need to be able to pat it on and also push it around easily, especially to get it out to the edges of the leaf.
9. Start patting on small handfuls of hypertufa. Work from the center of your leaf, out to the edges. Keep the thickness of the 'tufa consistent -- apply at least a ¾" layer. Be careful not to push too hard -- don't tear a hole in the leaf.
10. Optional application method: put down a layer of the 'tufa mixture and
then add strips of drywall joint tape, hardware cloth, or chicken wire. Spread another layer of 'tufa on top of the reinforcing material to completely cover it.
11. Make very sure to gently PUSH the 'tufa into the leaf. You want to capture all the veins and crevices. This is what will make it realistic when it cures!
12. Smooth off the 'tufa on the leaf's edge. The more time you take to follow the shape of the leaf, the more realistic it's going to look when completed. Make sure you've applied the 'tufa thick enough around the entire edge so it won't crack off.
13. When the leaf is covered with 'tufa to your satisfaction, mist thoroughly with water and cover it completely with plastic wrap. Secure the edges of the plastic wrap with a ring of more sand, or other objects -- anything that will keep the moisture sealed in and air flow out!
14. After approximately 48 hours, if you can barely scratch the 'tufa with your fingernail, it's ready to be turned over in order to remove the leaf. Be careful when grabbing your new 'tufa leaf! The edge you're holding is usually the most likely part to break off as you pick it up. If you've cast a really large (and heavy) leaf don't take a chance at breaking it. Ask a friend to help you flip it over.
Still curing, damp hypertufa Ligularia leaf casting 15. Hopefully, the real leaf will peal away from the casting. However ... sometimes parts of the leaf just stay stuck. In this case, use a sharp pointed knife, awl or similar object to pick out the pieces. You may have to scrape or use a semi-soft bristle scrub brush to remove the rest.
If some of the leaf pieces or stems still don't come out, just leave your 'tufa leaf alone for a few days. The real leaf will dry out and be easier to pull off or spray out with a hose.
16. Continue with proper curing techniques for about the next month. Make sure you have familiarized yourself with all the curing procedures as explained in "The Hypertufa How-To Manual"
SHOULD YOU PAINT, STAIN OR SEAL YOUR NEW LEAF ... OR NOT ?The whole idea of working with hypertufa is that it replicates real Tufa over time. The peat moss decomposes and leaves little holes and crevices. So, if this is your intention, do not paint or seal it. You can stain it, though. A watered down stain does not necessarily stop the peat moss from decomposing.
However, many crafters do want to paint their leaves a vibrant color, or wish to apply a few coats of sealant. Be aware this will more than likely defeat the purpose of using a 'tufa recipe.
All this being said, there is no "right way" or "wrong way" with this project. Your creativity will dictate how you finish off your leaf.For the best colorant and stain information, please refer to the color and stain charts on my website: The-Artistic-Garden.com Colorant Charts Or, please visit: www.The-Artistic-Garden.com/concrete-stains.html