Gardening Resources

Gardening resources we rate

GardenCalc is a free set of UK gardening calculators, but the calculators do not work in a vacuum. This page collects the directories, communities and data sources we genuinely rate: the places we point people to, and the authorities our numbers are checked against.

Spotted a broken link, an out-of-date figure, or a source we should be citing? Email hello@gardencalc.uk and we will check it. We only list resources we would actually use ourselves, and we correct things when we get them wrong.

UK gardening directories and communities

A handy way to find local gardening services, suppliers and fellow gardeners. These are UK-focused gardening directories and communities worth a look:

• The Garden Directory is a human-reviewed directory of UK gardening and landscaping businesses, blogs and resources. Because a person checks each listing before it goes live, the quality holds up far better than the big automated directories. Good first stop if you need a local trade you can actually vet.
• Garden Forum: a long-running community where UK gardeners swap advice and answer each other's questions. The archive runs deep, so odds are your exact problem has been asked and answered by someone gardening in the same climate and soil as you. Worth searching before you post.
• Landscape Juice Network is the UK network for professional landscapers and gardeners. If you are pricing up a bigger job like a patio, decking or a full garden redesign, reading how the professionals discuss materials and costs is a genuinely useful reality check before you get quotes in.
• Gardenzine is a free UK gardening magazine with a classified directory. Practical seasonal articles written for British conditions, plus classifieds that lean toward smaller specialist suppliers you will not find on the high street.

Allotment communities

Some of the most practical growing knowledge in the UK lives on allotment sites, and some of the earliest links to GardenCalc came from allotment societies who found the calculators useful. Three places worth knowing:

• Allotment & Gardens is John Harrison's long-running site, and one of the deepest wells of practical month-by-month growing advice in the UK. His Garden Advice by Month pages are the written companion to what our planting calendar does with numbers, and his vegetable growing books have taught a generation of plot holders.
• The National Allotment Society: the national body for allotment holders. Guidance on getting a plot, your rights as a tenant, and growing advice aimed at productive plots rather than ornamental gardens.
• Allotment Online is a directory and community hub for UK allotment sites and societies, useful for finding a plot near you and connecting with your local society.

Trusted data sources

Every figure in our calculators is checked against published UK authorities. If you want to dig into the source data yourself, start here:

• RHS — Royal Horticultural Society: sowing and planting calendars, lawn feeding rates and pest advice. When a GardenCalc figure touches on what to plant and when, the RHS guidance is the benchmark we check it against. Their advice pages are free and cover almost every plant you can grow in the UK.
• Met Office — UK climate averages: the 30-year frost and rainfall data behind our frost date and water butt tools. This is the primary source for UK climate normals, and it is the reason our frost dates change with your postcode rather than giving everyone the same generic answer.

Our free calculators

Looking for a specific tool? Every GardenCalc calculator is free, needs no signup, and uses UK units and product sizes:

• Grass Seed Calculator: how much grass seed for a new lawn, overseeding or bare patches.
• Compost Calculator: compost in litres, bags and bulk bags for any project.
• Topsoil Calculator: topsoil for raised beds, borders and containers.
• Gravel Calculator: gravel and decorative stone for paths, drives and patios.
• Frost Date Calculator: your last and first frost dates by UK postcode.
• Planting Calendar: what to sow and plant each month across 30+ UK vegetables.

See the full list of calculators or read more about GardenCalc.

Our sister site

For jobs beyond the garden, try HomeCalc.uk, which applies the same free, no-signup approach to home improvement calculators.