Once a botanical inclusion sheet has been couched onto a felt or board and pressed to remove excess water, the drying stage begins. How the sheet dries has a significant effect on its final character: flat restraint-dried sheets have a different surface from air-dried sheets that have cockled and then been pressed flat, and the translucency of the finished paper depends partly on the consolidation of fibres during drying.
Why Drying Method Matters for Inclusions
In plain sheets of handmade paper, the drying method primarily affects flatness and surface texture. In botanical inclusion sheets, it also affects how the embedded leaf integrates visually with the surrounding paper. A leaf embedded in a sheet that dries tightly restrained against a flat board will be pulled flat as the surrounding fibres shrink, creating tension around the leaf edges that can cause puckering or, in extreme cases, small tears in the paper at the leaf margin.
A sheet that air-dries without restraint allows both the surrounding fibres and the leaf to move somewhat independently during drying, which typically results in a more natural, less forced relationship between the inclusion and the paper — but also in more overall cockle in the sheet.
Method 1: Free Air Drying
In free air drying, the couched sheet is removed from the felt or board and hung or draped over a line, a wooden dowel, or a mesh drying frame. The sheet dries from both surfaces simultaneously, which is efficient but allows shrinkage in all directions, producing cockle — an irregular, wavy surface texture that is characteristic of unsupported air-dried handmade paper.
For botanical inclusion paper, free air drying can produce attractive textured results. The cockle around the leaf gives a three-dimensional quality. However, sheets dried this way generally cannot be used flat without subsequent pressing.
In Polish summer conditions (high ambient humidity), free air drying can take significantly longer than in dry conditions. Ensuring adequate air circulation around the drying sheets prevents uneven drying that accentuates cockle on one face relative to the other.
Method 2: Board Drying
Board drying involves transferring the couched, pressed sheet directly from the felt onto a smooth, rigid board — typically a sheet of acrylic, glass, or sealed wood — and allowing it to dry while adhered to the board surface. As the wet sheet dries, it adheres lightly to the board surface, and the surface tension during drying pulls the fibres flat as they contract. The result is a much flatter sheet than free air drying produces.
The sheet is released from the board by sliding a thin, flexible palette knife or similar tool under the edge and gently lifting. Sheets release naturally once fully dry in most cases, though sheets with high cotton content and smooth boards may require slightly more effort.
Method 3: Restraint Drying Between Boards
Restraint drying involves sandwiching the pressed couched sheet (still on its felt) between dry felts and rigid boards, applying pressure, and allowing it to dry in this compressed state with the pressing boards changed periodically as they absorb moisture. This method produces the flattest results and the most even consolidation of fibres, but it has a specific interaction with botanical inclusions.
The pressure applied during restraint drying presses the leaf more firmly into the paper matrix, which can improve the visual integration of the inclusion but can also cause the leaf to flatten excessively if it is not already thoroughly pressed. Thick or underpressed leaves may form raised areas that create uneven pressure points in the stack.
Pressing After Drying
Regardless of the initial drying method, many botanical inclusion sheets benefit from a final pressing to flatten cockle and consolidate the surface. A simple book press or two boards with weights works adequately for studio use. Place the sheet between smooth, absorbent boards (dampening them slightly before pressing can help relax cockle without rewetting the sheet) and apply moderate weight.
Allow the pressed sheet to remain under weight for at least 24 hours. Release, allow to equilibrate to ambient conditions, and assess flatness. Sheets with significant botanical inclusions may require a second pressing cycle.
Humidity Considerations in Poland
Poland's seasonal humidity variation directly affects drying time and the behaviour of finished sheets in storage. Sheets pressed flat during winter heating season (low indoor humidity) may cockle slightly when humid summer air returns. For use or storage, keeping finished sheets in an environment with stable humidity — or storing flat in a sealed portfolio with silica gel — helps maintain the pressed condition.
Translucency and the Inclusion
One of the distinctive visual properties of botanical inclusion paper is the silhouette visibility of the embedded material when the sheet is held to light. This translucency is a function of sheet thickness, fibre type, and how densely the fibres have consolidated. Thinner sheets produced from more beaten pulp show the oak leaf silhouette most clearly. Thicker, less beaten sheets may obscure the inclusion entirely from the back but show it as a visible surface texture from the front.
Drying method affects translucency indirectly: restraint-dried sheets, with more consolidated fibres, tend to have a slightly different transmittance characteristic than air-dried sheets of nominally the same thickness.
