Greenhouse Direction: East–West or North–South?
Greenhouse site planning
The midday sun is to the north throughout New Zealand, but its height and the direction of sunrise and sunset change with the season. Choosing between an east–west and a north–south ridge therefore involves more than finding the sunnier side of the garden: each direction presents different glazed surfaces to winter noon, morning and afternoon light. Nearby shade, greenhouse shape and the beds you plan to use still determine whether that difference helps.
What east–west and north–south describe
On a rectangular greenhouse, east–west or north–south normally describes the ridge line: the high line running along the roof. An east–west ridge leaves the long sides facing roughly north and south; a north–south ridge leaves them facing east and west. The gable ends face the other pair of directions. Rotating the same footprint changes which glazed surfaces receive direct sun and when, but does not add daylight to the property or remove a nearby obstruction. The entrance may face another way; it is the ridge, not the door, that this comparison describes. In casual use, facing can also mean the front, so keep those details separate.
Record the actual bearing on your sketch rather than forcing an imperfect angle into a compass label; garden boundaries, access or the house may make a slight diagonal more workable. Keep alignment separate from whether the site is sunny enough. A house, fence, mature tree, hill or neighbouring building can shade either option, while a clear position can still have brighter and darker sides. First identify when direct light reaches the proposed footprint, then compare both ridge lines against those same conditions. This avoids treating orientation as a cure for existing shade.
How the sun moves over New Zealand through the year
In New Zealand, the sun is north at solar noon throughout the year. Around midwinter it sits low above the northern horizon; it climbs higher by the equinoxes and reaches its highest daily arc near midsummer, while remaining north at noon. Sunrise and sunset points shift too: roughly north-east and north-west in winter, east and west around the equinoxes, and south-east and south-west near midsummer. The exact angles change with latitude and date, and a nearby ridge may hide part of the horizon. Solar noon is the sun’s daily high point, not necessarily 12 pm on the clock.
This matters because the north-facing roof plane is not a winter-only feature: its angle to the sun changes through the year. On an east–west ridge, the main roof planes face north and south. On a north–south ridge they face east and west, receiving direct rays at different times, while the north-facing gable can meet midday sun. Summer’s higher path may reach surfaces that low winter sun misses, and sunrise or late-day rays arrive from different compass directions. Roof pitch, glazing and obstructions determine what reaches the beds, so use the sun path to compare opportunities, not to predict guaranteed growing conditions.
East–west ridges and the northern roof plane
An east–west ridge has a long north-facing roof plane above its north side, with the opposite roof plane and side facing south. At New Zealand solar noon, sunlight comes from the north all year; in winter it is low, so a clear northern horizon allows that long north-facing plane to receive direct sunlight. This can be worth testing if winter growing matters. It only helps when the north side is not blocked by a house, trees or fence; low winter sun makes such obstructions especially important. Roof framing, crop height and the less-exposed side still affect the interior light pattern.
Near midsummer the noon sun is much higher, changing the angle at which light reaches the roof; sunrise and sunset also occur further south than in winter. The north-facing plane is not a guarantee of identical exposure year-round, and the south-facing side is not necessarily dark at every hour. Draw the beds under both roof planes. If you are considering the Classic aluminium greenhouse range, listed sizes run from 3.77 m² to 28.08 m². Use the dimensions of the exact option, because its area alone does not show the footprint. Keep that same footprint when you rotate the sketch.
North–south ridges and light through the day
A north–south ridge puts the long roof planes towards east and west. Direct sun can reach the eastern plane in the morning and the western plane later, so the illuminated side changes through the day. That may suit a bed layout where light moving across the greenhouse is useful, but it does not guarantee equal conditions: the sun’s height, glazing, frame members, tall crops and nearby shade can still leave uneven patches. In New Zealand the midday sun remains north, so it faces the north gable rather than directly facing either long roof plane. Check whether that end has a clear view of the sun.
In winter, low northern sun may enter through an unobstructed, glazed north end and travel into the greenhouse. How far it reaches depends on the end glazing and framing, the structure’s length, bed height and the sun’s angle; do not assume the entire interior receives the same light. A northern building or hedge can remove that route. The Limited Edition greenhouse range covers listed areas from 3.77 to 28.08 m². Use the outline and end details of your preferred size to compare the north end’s winter exposure with the morning and afternoon pattern along the long sides.
Compare seasonal shadows on a site plan
Draw both alignments on a scaled site plan, with north clearly marked and the same greenhouse footprint rotated through 90 degrees. Add fixed obstructions—house, fence, trees, shed and landform—and note their position and approximate height well enough to estimate their shadows. Compare the site in winter and summer, ideally near the solstices, and add equinox conditions as a middle point. For each season consider morning, solar noon and afternoon. A single midday observation misses how shadows move across the garden as the sun moves from morning to afternoon. If a tree is deciduous, note its leaf-on and leaf-off canopy too.
Photograph from the same spot and label the date and time, or use a sun-path tool to estimate seasons you cannot observe; check its result against real buildings and trees that a generic chart cannot include. Mark shade on the future beds, not just the greenhouse outline, and note which areas remain in direct light. Compare when shadows clear and return, rather than relying on one snapshot. If the Prestige greenhouse range is on your shortlist, its listed area runs from 3.77 to 28.08 m². Confirm the chosen model’s dimensions and trace its footprint onto both versions of the plan.
Fit beds, crop heights and access to the light
Orientation should support the growing plan, not dictate it. Draw each bed, the main path, shelves, supports and likely mature crop heights inside both candidate layouts. Compare beds running along the ridge with beds crossing it; low winter sun from the north can send a tall crop’s shadow southwards, while morning and afternoon light arrive from opposite sides. There is no universal bed direction because crop height, season, spacing and glazing alter the result. A greenhouse used for different crops through the year may need different priorities, so mark the beds that matter most in each season.
Add the route from the garden to the door, room to carry a tray or soil, and the space needed to work along the beds. If storage is part of the plan, its exact position matters as much as total area; do not infer the internal layout from a model name. The Limited Edition greenhouse with storage is listed in sizes from 5.52 to 28.08 m². Use the selected option’s actual plan to see whether storage, beds and access still fit after rotation, and check the layout again with mature plants rather than an empty greenhouse.
A lean-to must work with its wall
A lean-to adds a fixed wall, so the greenhouse’s orientation is partly set by the building rather than chosen freely. The wall’s compass direction, its own shade and the amount of open sky in front affect when the glazing receives sun. A north-facing wall can meet midday light, but an eave, upper storey or nearby roof may still shade the greenhouse; a wall facing another direction has a different daily pattern. Draw the house and proposed greenhouse together, including the wall direction, overhangs and door access. The wall may not align with a compass axis, and the greenhouse cannot simply be rotated while keeping the same attachment. Do not assume attachment automatically improves light.
The lean-to greenhouse range lists options from 3.69 to 14.34 m². Check the selected unit’s footprint and openings against the actual building and the route to its door, then confirm any design requirements with the supplier. If the proposed support, base or connection needs assessment, ask the manufacturer or a qualified installer for advice specific to the building and site. A compass sketch helps with sunlight; it does not settle whether the wall or base is suitable.
When the ridge comparison does not fit the shape
The ridge comparison is clearest for a rectangular greenhouse with one long ridge. If a design has a square, multi-sided or otherwise unusual plan, map its whole footprint and identify the glazed faces, openings and growing zones instead of reducing it to a single axis. Different surfaces may receive sunlight at different times, so an east–west label can conceal important differences. The relevant question is where direct light falls on usable growing space, not which compass label sounds closest. This matters especially where a tree or building shades only one part of a more complex shape.
If the Pyramid Greenhouse is on your list, do not infer its orientation from the name alone. Its listed sizes run from 5.53 to 18.9 m². Use the selected product plan to identify the outline, glazed faces and opening positions. For each possible rotation, compare its entry and growing areas with the shadows on your seasonal drawing. Where there is no single long ridge, mark the compass direction of each glazed face so you can relate the whole design to the sun’s changing position.
Check the full footprint in both directions
Check the complete footprint before committing to an axis. A garden may have room for the greenhouse length in one direction but not in the other once the doorway, approach path, working space and beds are drawn. Include projections, end sections and storage that belong to the exact model; total floor area is not a plan dimension. If the fit is close, measure boundaries and access on site, and confirm any construction or base requirements with an appropriate professional rather than applying a universal clearance or foundation rule. This is separate from how the sun reaches the roof, but it can decide which orientation is practical.
The T-Model Orangery Greenhouse is listed with area options from 16.52 to 30 m², which can help you think about scale but cannot replace an exact plan. Draw the particular outline in both positions. If it has projecting sections, a quarter-turn may move a door, path and growing zone in ways that a simple rectangle cannot show; even a narrower edge near a boundary can alter access. A measured sketch also makes it easier to compare sunlight without quietly changing the proposed size between the east–west and north–south versions.
Choose the axis that suits your growing plan
Set your seasonal priorities before choosing an axis. If winter growing matters most, compare how each layout receives low northern sun: through the long north-facing plane of an east–west greenhouse or through the north end of a north–south greenhouse. If your main growing season is summer, give more weight to the morning and afternoon pattern and the beds you will use then. For year-round growing, neither season should decide the layout on its own. Identify which beds matter most in each season and compare their exposure, rather than choosing the direction that looks brightest in a single observation.
Bring the seasonal comparison together with your access plan. Ask which arrangement leaves a usable entrance and path alongside the beds you intend to grow in. For a larger candidate, the Spacious Greenhouse range is listed from 47 to 70 m². Use the exact product plan to assess the whole growing and access layout, including any areas that sit beyond the brightest part of the site. If neither rotation works well, consider a different position or footprint rather than forcing a compass preference.
Frequently asked questions
Which ridge direction is best in New Zealand?
Neither is best for every site. An east–west ridge offers a long north-facing roof plane for the midday sun, including low winter sun. A north–south ridge puts the long roof planes towards morning and afternoon light and may admit winter sun through a clear north-facing end. Check local shade, the greenhouse shape and your bed layout before choosing.
Does an east–west ridge get more winter sun?
It can make a long north-facing roof plane available to low winter sun, but that advantage depends on an open northern horizon. A house or tall tree to the north can cast shade across it. A north–south greenhouse may receive winter light through a clear, glazed north end, depending on its length and internal layout.
Does a north–south ridge give more even light?
Not necessarily. Its east- and west-facing roof planes receive direct sun at different times, but shadows from the frame, nearby objects and tall plants can still leave uneven patches. The low winter sun also reaches a north-facing end differently from the long sides. Draw your beds and check the light at more than one time of day.
Should greenhouse beds run parallel to the ridge?
There is no single bed direction that suits every crop and season. Compare beds running along the ridge with beds crossing it, and mark mature crop heights so you can see where shadows fall. Include the path and entry in both layouts: a bed that catches more sun may still make the greenhouse awkward to use.
How can I compare orientations before buying?
Draw the exact greenhouse footprint on a scaled site plan in both directions. Mark north, nearby shade sources, planned beds and access routes, then compare morning, solar-noon and afternoon light in winter and summer. Seasonal sun-path information can help when you cannot observe every period. Confirm the dimensions of the specific model before making a final choice.
Neither axis has a nationwide advantage. In New Zealand the midday sun is north, so an east–west ridge presents a long north-facing roof plane to it; a north–south ridge receives light on its east- and west-facing roof planes at different times and may admit winter sun through a clear north end. The useful choice is the one that works with the actual shadow pattern, beds and access on your site. Comparing both rotations with the same footprint and seasonal assumptions makes the trade-off clear.
