Flowers & Container Gardening
No garden bed required — a pot, the right substrate and a sunny spot will carry a season of blooms. Three things decide whether it works: drainage, sun, and feeding.
The short answer
1. A drainage hole is non-negotiable. Gravel in the base of a sealed pot does not substitute for one.
2. Go one pot size bigger than you think. Small pots on a hot balcony dry out by lunchtime.
3. Containers need feeding. Every watering flushes nutrients out the bottom. Beds do not have that problem.
Pot size and drainage
Container volume decides how often you water far more than the weather does. Use this as a starting point for a sunny patio or balcony.
| Pot | Suits | Watering in full sun |
|---|---|---|
| 6–8 in | A single marigold, pansy or compact annual | Daily, sometimes twice in a heatwave |
| 10–12 in | Three or four annuals, or one small perennial | Every one to two days |
| 14–16 in | A full mixed planting — thriller, filler, spiller | Every two to three days |
| 18 in and up | Shrubs, dwarf trees, anything overwintering | Twice a week, more in peak summer |
The gravel myth: a layer of gravel at the bottom of a pot does not improve drainage — it raises the saturated zone closer to the roots. Use a substrate that drains and a pot with a hole in it. That is the whole solution.
Sun and feeding
Six hours, minimum
Most flowering annuals, marigolds included, need at least six hours of direct sun to bloom properly. They survive partial shade, but they flower sparsely in it. South and west-facing balconies do the job.
Feed fortnightly
A container is a closed system that you flush every time you water. Molly’s mixes ship free of fertiliser deliberately, so start a balanced liquid feed at half strength every two weeks through the growing season.
Not sure which one — three mixes, one root type each: Aroid for leafy tropicals and most patio annuals, Succulent for anything that wants to dry fast, Orchid for epiphytes. Match the mix to the root and the watering looks after itself.
Read next
Soil & potting basics
- Best soil for indoor plants — how to match the right mix to each plant you grow in a container.
- Best soil for succulents & cactus — the gritty, fast-draining mix container succulents need so roots never sit wet.
- Potting soil vs. potting mix — why container plants do better in a soilless mix than in dense bagged soil.
Container gardening
- 10 best potted plants for containers — beyond marigolds, ten reliable performers for sunny patios and balconies.
Common questions
What is the best soil for marigolds in pots?
A free-draining mix with a balanced coir and perlite base. Marigolds rot in waterlogged substrate, so it has to drain quickly between waterings. Avoid pure topsoil or compacted garden soil — both hold far too much water in a container.
How much sun do marigolds need?
Full sun, at least six hours of direct light a day for the best blooming. They tolerate partial shade but flower sparsely without strong sun. South or west-facing balconies work well.
Can marigolds survive winter outdoors?
Most common marigolds (French and African) are annuals and die at the first frost. Calendula, sometimes sold as “pot marigold”, is a different species and somewhat hardier. To overwinter, bring containers indoors before the first hard frost.
A substrate that lasts the season
Drainage that works from the first watering to the last, and structure that does not collapse by August.
Browse Molly’s mixes → · Soil finder quiz
More care guides
Orchid care · Succulent & cactus care · Soil & substrate basics · Propagation
