Ground cover is basically the “dirt” and the “vegetation” that covers the surface of your layout and hides all the white plaster or pink foam that covers your terrain. It is a very important part of your model train scenery and can make or break the realism of your model railroad depending on how well it’s done.
Ground cover is divided into three basic types:
• Low – includes the coloring of your layout surface and the addition of small grasses, small weeds and other plants that are low to the ground.
• Medium – includes medium-sized underbrush, weeds, vines and other plants.
• High – includes larger bushes, grasses and shrubs, but not trees.
Low ground cover
You should start by painting or staining the layout surface with tan or earth color. I would use this color in all areas where you will be adding ground cover. Some say to use green paint in areas where you will have a lot of green grass or foliage, but I never did this. When I wanted to model green grass, I just added green ground foam to the tan colored surface and this worked well. I think it’s even better because if a little brown earth peeks through your grass cover, it’s more realistic.
Many model railroaders like to use something called "ground goop" for this step. This is basically a mixture of coarsely textured plaster and/or paper mache or vermiculite with water, and which may or may not be mixed with a choice of color, usually either earth or grass colors. (If you decide not to add color to the mixture, you can add the paint or stain after you've spread it.) When spread on the surface of the plaster cloth or other scenery base, the ground goop provides a thick layer of cover which hides all the holes in the plaster cloth and serves as a realistic, textured surface upon which you can apply the rest of the ground cover as follows.
Ground foam, incidentally, is the stuff you buy at hobby stores or online that simulates grass. Older model railroaders used to use sawdust stained with different colors for this use. However, I think most people now just use purchased ground foam. You can buy this in many shades or green, tan, autumn colors, or as blended turf which is one of my favorites. You should have a selection of these available when you're ready to put down your ground cover so you can use a variety of colors and textures.
If you prefer, while the paint is still wet, you can begin adding the first layer of ground foam to the wet paint. Work in small sections so the paint doesn’t have a chance to dry before adding the ground foam.
I like to use blended turf for most of the initial application because it looks more realistic for turf around railroads. Plain green would be best for well-manicured lawns and golf courses, not along railroad tracks. You can add various shades of green or tan to the blended turf later depending on whether the scene you’re modeling is in a forest, a grassy meadow or a rocky hillside that doesn’t grow much grass. If you’re doing a desert scene, you will most likely be using more tan ground foam with little pockets of medium green underbrush here and there.
I don’t like to use canister shakers to put down foam. You have very little control over where it goes and you usually end up with it being in places where you don’t want it. Instead, I like to grab a pinch of the ground foam between my first finger and thumb and gently sprinkle the foam over the area that I want to cover. Granted this may be somewhat tedious, particularly if you have a large area to cover, but the control of where the foam goes is much better. (Note that lately, I have been modeling in N scale so I don’t have a lot of room for error when it comes to putting down ground cover. If you’re modeling HO or O scale, this might not be so much of an issue and you can use the canister to cover large areas if you wish.)
Another method is to wait ‘till the paint dries, then apply the ground foam after brushing on a layer of diluted white glue or flat matte medium.
Having done all of these a time or two, the method I think is best is to let the paint dry, then sprinkle the dry ground foam into the appropriate area, then use very diluted white glue (1 part white glue, 1 part isopropyl alcohol [rubbing alcohol] and 4 parts water) with a pipette, close to the surface, to drip the glue on the ground foam, gently, to avoid scattering the foam particles. The diluted glue will spread very thinly and evenly over and under the ground foam. You should put enough glue in the area slowly and gently to saturate the ground foam so you can see the white glue coming up through the ground foam when you’re finished. Let this dry overnight.
The next day you can add more ground foam, perhaps different shades, blended in to the first layer in various places. When you’re happy with the results, drip on the glue like you did before.
Remember that a variety of shades and textures is much more realistic than one color and shade for all your ground cover.
As with a lot of things we do, it’s often a good idea to have a reference photo of the kind of scenery you’re trying to model.
Also, remember if you make a mistake, or it doesn’t look the way you want it, that’s okay. Just apply a new layer of a shade you might like better over top of the old layer and re-glue it. One advantage of spreading the ground foam on a dry surface before fixing it with the glue is that if you don’t like the result, you can vacuum it up before it’s been glued down.
What about hillsides that won’t hold the ground foam before you can apply the glue? Here, you will most likely have to brush or spray on the glue before you sprinkle on the foam.
There is another way to do it, however, particularly on steep areas and mountainsides: Make a mixture of ½ strength white glue (or flat matte medium) and ground foam together into a putty consistency. Then use this mixture to smear on the sides of the mountain where you want vegetation. Before it dries, you can add a variety of other shades of ground foam as well by sprinkling it over what you’ve already put down. The white glue or matte medium will dry clear and your vegetation will be left in place.
Medium ground cover
The next thing to do is add coarse turf to different areas where you don’t want that “mowed” look, which, around railroads is usually most places. This will add a variety of texture to the area to improve realism. After you’ve put down some coarse turf, apply a little of the fine turf over it slightly to help blend it in. Glue these down in the same way as described above.
I generally don’t like to use glue-type sprays because they usually blow the ground foam all over where you don’t want it to be, and because you end up getting the glue all over your track (unless you’ve been smart and covered your track before starting this scenery process).
Now you can apply underbrush to areas along your track that you want to appear overgrown and not well maintained, and also in areas close to trees and forests.
Add vines to rocky areas, tunnel portals or retaining walls. Some people like to use polyfiber for ground cover. I myself don’t think it looks that realistic, but if you add ground foam to it after it’s laid, you could probably get away with it, especially if it’s mixed in with a lot of other underbrush, foliage, trees, bushes, etc.
High Ground Cover
Adding bushes and shrubs to your ground cover is the next step and adds even greater realism to your scenery. These should be placed at random along your tracks, throughout the countryside - often in clumps - along fences, and as a front line for forests. They also go well along creeks, rivers and natural lakes. In addition, you will use bushes and shrubs as part of the decorative landscaping around houses and other buildings. These items can often be glued separately by adding a drop of white glue to one side of the bush and planting it where you want it on the layout.
You can purchase these bushes as clump-foliage, or you can use lichen for many of your bushes and shrubs. Lichen can be purchased at most hobby stores and craft stores and is easy to use. Just break it up into small pieces and plant them anywhere you want this kind of foliage. It looks more realistic if you apply a little sprinkle of fine turf on the lichen to look like small leaves.
If you want to add small bushes to a hillside, break a toothpick in half, paint it brown or gray, slide a piece of lichen onto the toothpick, put a drop of glue on the end of the toothpick and stick it onto the hillside.
Lichen may dry out after a while, but it usually retains its color and shape for years unless you mess with it; but it would be easy to replace individual pieces as you need them.
You can also find bunches of dried vegetation in craft stores that you can use if their tips look like the shapes of small bushes. Just cut off and discard their stalks, dip them in glue, sprinkle on ground foam, and glue them to your scene wherever you need a bush.
Once again, the more variety you have in the types of plants you use the more realistic the model scenery will be.