Lesson two, and this is where the garden starts to exist. Everything you ever place in GardenCAD, a bed, a fence, a patch of seed, a tree canopy, is drawn with the same gesture. You choose whether you are drawing a region or a planting, you choose a geometry, and you draw. That is it. Learn the gesture once here and it carries through every remaining lesson without modification, which is why this lesson is worth taking slowly even though it looks like the simple one. Along the way you will meet the decision the editor asks you to make the moment a shape closes: is this bed, or is this structure? That single question is what tells the solar model whether light passes through the thing you just drew or stops at it, and it is the reason a garden plan can tell you anything at all about shade.

Three objectives. First, you will be able to draw a region in all three geometries: a polygon by clicking each vertex and closing on the first, a rectangle by dragging corner to corner, and a circle by dragging out from the centre. You will also know the two keys that end a shape, Enter to close and Escape to cancel, because a half-drawn polygon you cannot get rid of is the most common early frustration. Second, you will be able to classify a closed region as a bed or a structure, and say what each one means to the model. Third, you will be able to edit a region after the fact: move its vertices, change its height, restack it against overlapping shapes, and combine two shapes with merge or subtract rather than redrawing a complicated outline by hand.

The word to learn is region. A region is any closed area you draw on the ground, and it has exactly one property that matters more than all the others: its kind. A bed is plantable ground. Plants go in it, the guided planter will fill it, and light passes over it freely. A structure is anything that occupies space and blocks light: a house, a shed, a fence, a wall, a raised planter's side, a paved path. Give a structure a height and it throws a shadow, and the length and direction of that shadow come from the site you set in Lesson one. That is the whole model in one sentence. You are not drawing pictures of a fence, you are telling a solar calculator that something two metres tall stands on this line, and everything the editor later says about shade is downstream of that.

Five steps to a classified region. First, set the Plant and Region slider near the top of the tool rail to Region. The same rail draws plantings when that slider is on Plant, which is why the slider exists at all. Second, choose a geometry: polygon, rectangle, or circle. Third, draw. For a polygon, click each vertex in turn and click the first vertex again to close it, or press Enter. For a rectangle or a circle, press and drag. Hold Shift while dragging a rectangle to lock it square. Fourth, classify. The instant the shape closes a small picker appears at the cursor offering Bed or Structure. Click one, or press B or S, and Escape dismisses it if you want to decide later. Fifth, adjust in the inspector: a structure needs a height before it casts anything, and a raised bed takes a base and a height too.

Two things about polygons that save real time. The first is that a polygon segment does not have to be straight. While you are mid-draw, pressing L makes the next segment a line and pressing A makes it an arc, so a curved bed edge is drawn in the same gesture as a straight one rather than approximated with twenty tiny clicks. The second is that you rarely need to draw a complicated outline in one go. Draw two simple shapes that overlap, select both, and right-click for Merge to fuse them into one region. Subtract does the opposite: it cuts the second shape out of the first, which is how you put a path through a bed or a pond in a lawn without tracing the resulting outline by hand. Between arcs and boolean operations, almost every awkward garden shape is two easy shapes and one menu item.

Four things that go wrong early, and what to do instead. People draw a fence and wonder why nothing is shaded: a structure with no height is a line on a plan and nothing to the model, so set the height. People try to trace a complicated bed in one polygon, lose their place, and start again: draw two simple shapes and merge them. People get stuck mid-polygon with a shape they cannot escape and reload the page, losing work: Escape cancels the shape you are drawing and right-clicking mid-draw does the same. And people redraw a region because a corner is in the wrong place: the select tool gives every vertex a handle you can drag, so almost nothing needs to be drawn twice. None of these are hard once you know them, and all four cost somebody an afternoon the first time.

Three things from this lesson. One gesture draws everything: set the slider to Region or Plant, pick a geometry, and draw, with Enter to close and Escape to cancel. That gesture does not change for the rest of the course. The bed-or-structure question is the whole solar model in one click, and a structure without a height is not a structure as far as the shadows are concerned. And nothing you draw is final: vertices have handles, heights are editable, stacking order can be changed, and merge and subtract exist so you never have to trace a complicated outline by hand. Next lesson we use those same tools in reverse, tracing a garden that already exists from a photograph, and setting it to true scale with a single real measurement.