Plant Spacing

Having plants spaced properly allows plants to grow to their fullest potential. A lack of space causes health problems, while too much space causes problems for maintenance. Learning how to judge how much space your plants need will help you make better decisions while gardening, designing a garden, and planning for future garden projects.

How do I space my plants properly?

Space requirements for common garden plants are often found on the back of seeds and labels on pots in nurseries. They can also be found online and on our plant pages.

A good visual rule of thumb for plant spacing is to plant so the tips of the leaves from one mature plant are 2-4 cm from the tips of the leaves of another plant. This usually can be estimated as:

• Around 5-10cm between seedlings for small leafy vegetables like lettuce and cai xin

• 15-30cm for small shrubs like Thai basil and lady's finger

• 2 metres or more for small trees like guava and chiku

Measuring out your planting space and marking how many plants you can grow beforehand will make direct seed sowing or transplanting more straightforward. However, poor spacing can also be fixed by thinning your plants for overcrowded areas, or interplanting for plants that are growing too far apart.

Thinning overcrowded plants

Many gardeners tend to scatter their seeds haphazardly in their planting areas or put multiple seeds in a single seedling tray cell. This will cause overcrowding and force plants to compete for light, water, and soil nutrients available within a given area. This in turn leads to several problems, including:

• Etiolation

• The rapid spread of pests and disease

• Stunted growth

• The death of less competitive plants

Thinning is the act of removing extra plants so that the remaining plants can grow to full size. This is best done at the seedling stage before transplanting, or just after germination. Vegetable gardeners who have sown too many seeds often thin out the weaker seedlings to be eaten as microgreens or transplant them elsewhere to fill gaps where other seedlings have died or been eaten by pests.

Interplanting

Pests, harsh weather and poor planning can sometimes result in large gaps between your plants. This tends to result in maintenance problems like:

• Exposed soil eroding away

• The faster evaporation of water from exposed soil

• Weeds growing in between plants

• Not maximising your garden space

Interplanting is the act of planting in between existing plants. Many edible gardeners will transplant in spare seedlings of the same plant, but growing companion plants in these gaps can also be considered to bring additional benefits to your garden, including improving soil fertility, attracting pollinators, and reducing soil erosion.