The basis of any print is a matrix which carries the ink to the paper, and when this matrix is stable, such as a metal plate or a block of linoleum, an edition of prints can be numbered from this matrix. If, however, the matrix is unstable, that is, obliterated by the act if printing, or shifts in such a way that pulling an exact (number-able) print is not possible, the resulting print is a monoprint. These are not editioned because each is different and so does not bear a number (1/1 is a mistake in nomenclature).
My botanical prints are monoprints by this definition, and they also are a part of a class of prints called direct prints. This is a type of printing in which an object is given a coat of ink, then touched to the paper to draw off a reversed image. The process is similar to a frottage, or rubbing in which paper is placed over an object and a chalk or graphite stick is rubbed over the object to yield an impression on the intervening paper. The main difference is that the monoprint is reversed while the frottage is a correct and accurate rendition.
The first prints I ever made, in the early 1990's, were fish prints, or gyotaku (Japanese for gyo - fish; taku - taking an impression). The process is quite simple. Laying a fish on its side first blot off the excess moisture, then apply water-based relief ink with a roller until coated with a thin layer of ink. Then place a sheet of mulberry paper on the fish, a layer of waxed paper to smooth the transfer, and burnish by hand. When the mulberry paper is pulled off, a fine impression of the scales of fish is the result. Of course it takes considerable skill to make the fish print a work of art.
Botanical prints could be made in this way, but this would not be very effective. My method involves several steps. First the plant is pressed in herbarium press between newspaper and corrugated cardboard until it is dry and flat. This may involve several changes of newsprint if the plant material is full of moisture, and may take a month or more. When that is done I bring the specimen into the print shop. I take a sheet of plexiglas and roll out a thin layer of ink with a large roller. This ink is not the aqueous ink most people know from fountain pens, but rather a thick ink with the consistency of toothpaste. I carefully place the plant onto this inking platform so as to minimize overlap of the leaves. Covering with newsprint, I run this through an etching press. The pressure (about 600 lbs per square inch) drives the ink into the matrix of the plant. If some leaves overlap, they are repositioned and run through the press a second time. If that plant were delicate, say a rose petal, this process would destroy the plant material, rendering it useless for the next step. For this reason the plant must be rather sturdy. Ideal subjects are grasses which possess in internal architecture that keeps the structure intact. There are parallel veins which act like little I-beams to preserve the leaf blades. The roots, too, are usually very strong, so impression of the roots can be very intricate and beautiful.
Once the plant has been run through the press, it is imbedded into the ink layer, and must be delicately pulled up without breaking. This generally involves forceps and needle probes to extricate the plant in order to keep the specimen from fragmenting. When it is free of the bed of ink, I carefully flip it over and lay it onto a clean sheet of plexiglas, inky side upwards. Once positioned I use cotton swabs to place ink in any areas which did not take up enough ink, and clean the plexiglas of any stray marks which may have been laid down when the plant was positioned.
Taking a dampened piece of printmaking paper, I gently let it fall onto the inked plant. If it falls incorrectly, there is no possibility to reposition, so this step must be carried out precisely. When the paper is resting on the inked specimen, I cover with newsprint and run through the press to produce a print. This is laid on a drying rack or hung vertically on a rail suspended by magnets for a day or two before it can be safely handled. I think of it as a fossil of a plant on paper.
I use various kinds of paper for botanical monoprints depending on the type of plant and size of the specimen and the final effect I am striving for. For larger prints up to 44" the paper must be robust, such as BFK Rives, a fine absorbent paper from France with a weight of 250 or 275 gm/m-2. Somerset from Britain is a similar high=quality paper I sometimes use. This paper must be dampened before printing to form to the specimen and transfer a good quantity of ink. Dampening has the additional effect of embossing the paper with the form of the plant, a process that lends a subtle sculpturing and contouring that makes it seem as if the plant is actually present as a three-dimensional object. For a more delicate look, I use thinner papers: Japanese mulberry papers such as Kitakata, Hosho, or Okawara impart an Asian look to the result while brightly pigmented Tibetan papers like Lokta have an impactful saturated appearance. These thinner papers are run through dry and thus hold less embossing.
I mostly sign these prints on the back, preserving their character as reports from the biosphere whose true creator is Mother Nature. Thinner papers would show through, so these I mostly sign on the front. I try to title them with the Genus and species of the plant, but this can be a challenge since the grasses are difficult even for grass specialists who must examine tiny flower parts under a dissecting microscope.