Plant Spacing Calculator

Plant Spacing Calculator

Correct spacing prevents disease, reduces competition for nutrients, and maximizes yield. Triangular arrangement (staggered rows) fits about 15% more plants than a square grid in the same area.

Square vs triangular grid

• Square grid: plants are aligned in both rows and columns. Easier to weed but less space-efficient.
• Triangular grid: each plant sits in the gap between two plants in the previous row. 15% denser; better for raised bed square-foot gardening.

Tips for better spacing

• Spacing recommendations are on seed packets or plant labels
• Dense planting suppresses weeds but increases humidity, beneficial for some plants, harmful for others
• Place tall plants on the north side of the bed to avoid shading shorter plants
• Allow a 15-20 cm border around the bed for edge plants
• Companion planting can allow closer spacing, e.g. lettuce under tall plants like tomatoes

Common spacing reference

UK allotment culture and spacing traditions

The UK has over 330,000 registered allotment holders, with a waiting list of similar size in many councils. Allotment gardening in the UK has developed spacing traditions adapted to the typical 10-rod plot (250 sq m). The standard UK raised bed is 1.2 m wide (reachable from both sides without stepping on the soil), and most spacing references assume this format.

The "Square Foot Gardening" method (from Mel Bartholomew's 1981 US book, now widely popular in UK growing communities) uses a dense triangular grid: 1 plant per 30cm square for large vegetables, 4 per square for medium (lettuce), 9 per square for small (beetroot), and 16 per square for very small (radish, spring onion). UK gardeners commonly use grow bags (45-50 litres) as an alternative to ground spacing for tomatoes, cucumbers, and peppers, especially on patios and in greenhouse settings.