GrowSabzHow to grow nemesia in pots
Also called cape jewels, nemesia flower · Nemesia spp.
نیمیسیا
- ☀️ Sunlight
- 6–8hours daily
- 💧 Water
- 0.4 Levery 2 days, 5 L pot
- 🌡️ Ideal temp
- 15–24°C
- 🪴 Min pot
- 5 L15 cm deep
- 🧺 Harvest
- 56–70days from sowing
- ⚖️ Yield
- 0.02 kgper 20 L pot
Nemesia keeps producing once it starts. First picking comes around day 56, and the plant then crops for roughly 120 more days — but only if you keep picking. Blooms left on the plant is a signal to stop making more.
Short answer
Grow nemesia in a 5 litre container at least 15 cm deep, watering about 600 ml per 10 litres of soil every 2 days, and keep temperatures between 15 and 24 °C. First harvest comes 56–70 days after sowing.
Where to plant it
What size pot does nemesia need?
5 litres and 15 cm deep is the realistic minimum for a single plant. Pick a container below to see what changes.
| Container | Minimum size | Depth | Notes |
|---|---|---|---|
| Pot | 5 L | 15 cm | Ensure good drainage. Ideal for compact varieties. |
| Grow bag | 5 L | 15 cm | Provides good aeration for roots. |
| Open ground | — | 20 cm | Plant in well-draining soil. Space plants 15-30 cm apart. |
| Raised bed | 10 L | 20 cm | Excellent for controlling soil conditions and drainage. |
Watering
How often should you water nemesia?
Every 2 days through the growing season, at about 600 ml per 10 litres of soil — daily in hot weather, every 3 days when it turns cool. Water in the early morning. Base of plant works best.
Too little water
- wilting leaves
- stunted growth
- reduced flowering
Too much water
- yellowing leaves
- soft stems
- root rot
Avoid: waterlogging; letting soil dry out completely.
Climate
Can you grow nemesia where you live?
No hardiness zone needed — compare your actual temperatures against the plant's own limits.
| Ideal range | 15 – 24 °C |
|---|---|
| Survives | 0 – 30 °C |
| Germinates above | 18 °C — best at 21 °C, about 14 days |
| Flowers drop | above 28 °C, or below 5 °C |
| Sunlight | 6–10 hrs/day, best 8 |
| Frost | Highly sensitive — will not survive it |
The flower-drop thresholds matter more than the survival ones. A plant can be perfectly alive at 30 °C and still give you nothing.
How cold is too cold for nemesia? Check your temperaturesEnter your night low and day high — see if it survives, and if it will cropTimeline
Nemesia growing stages, day by day
Click any stage to see what's happening. Durations shift with temperature — a warm season runs roughly a quarter faster than a cool one.
Feeding
Fertiliser schedule for nemesia
Feed on the interval below, changing what you give as the plant shifts from making leaves to making fruit.
| Stage | What to use | Per 10 L | Every |
|---|
How to prepare each feed
Common mistakes
Why nemesia fails, and how to avoid it
- A container that is too small
Below 5 litres the root run is too shallow. The plant grows, flowers late, and drops whatever it sets because it cannot support the crop.
- Watering too lightly
A daily splash wets the top few centimetres and nothing else. Nemesia wants about 600 ml per 10 litres of soil — one deep soak beats three shallow ones.
- Ignoring the flower-drop threshold
Above 28 °C, or below 5 °C, flowers fall before setting. The plant can look perfectly healthy and still give you nothing — shade it through the hottest hours.
- Planting it beside Aggressive Herbs
Highly aggressive herbs like mint can quickly outcompete Nemesia for nutrients and space, especially in containers.
- Leaving it out through a cold snap
Nemesia is highly frost-sensitive. One night below 0 °C can end the plant outright — bring containers in or cover them.
Companions
What to plant with nemesia
Good neighbours
Creates a beautiful cascading effect in containers and attracts pollinators. Similar light and water needs.
Complements Nemesia with similar growth habits and continuous flowering, ideal for mixed displays.
Forms a low-growing carpet, suppressing weeds and attracting beneficial insects, while Nemesia provides vertical interest.
Known to deter various pests, including nematodes and some insects, benefiting nearby plants.
Keep apart from
Highly aggressive herbs like mint can quickly outcompete Nemesia for nutrients and space, especially in containers.
Plants with very high nutrient demands may deplete soil resources quickly, leaving Nemesia undernourished.
Nemesia thrives in full sun; pairing it with shade-loving plants will result in poor growth for one or both.
Problems
Nemesia pests and diseases
Each lists the weather that brings it on, so you know when to start checking rather than reacting once it's established.
Aphids humidity any · temp 15-25
Small, soft-bodied insects that cluster on new growth and undersides of leaves, sucking sap and causing distorted growth.
Whiteflies humidity >60% · temp >25
Tiny, white, winged insects that fly up when disturbed. They feed on sap, weakening the plant and potentially spreading viruses.
Spider Mites humidity <50% · temp >27
Minute pests causing stippling on leaves, which may turn yellow or bronze. Fine webbing can be seen on undersides of leaves in severe infestations.
Powdery Mildew humidity 50-70% · temp 20-27
White, powdery patches appear on leaves and stems, hindering photosynthesis and weakening the plant.
Downy Mildew humidity >80% · temp 10-20
Yellow spots on upper leaf surfaces with fuzzy gray mold on the undersides. Can cause leaf drop and plant decline.
Root Rot humidity any · temp any
Caused by overwatering and poor drainage, leading to wilting, yellowing leaves, and eventual plant death. Roots become soft and brown.
Botrytis Blight humidity >85% · temp 15-25
Grayish-brown fuzzy mold on flowers and leaves, especially in cool, wet conditions. Can cause flowers to rot and stems to die back.
Harvest
When to harvest nemesia
First picking falls between day 56 and day 70, and the plant then keeps producing for about 120 days. Pick often — what you leave on the plant signals it to stop making more.
How to tell it's ready
- Fully open flowers
- Vibrant color
How much to expect
Storing it: Use fresh for display; not typically stored.
Questions
Nemesia: common questions
How long does nemesia take to grow?
About 75 days from sowing to the first harvest, with picking usually starting between day 56 and day 70. It then keeps producing for roughly 120 more days. Warm weather pulls that forward; cool weather pushes it back.
What size pot does nemesia need?
At least 5 litres and 15 cm deep for one plant. A raised bed wants 10 litres of soil and 20 cm of depth.
How often should I water nemesia?
About 600 ml per 10 litres of soil, every 2 days in normal weather — daily when it is hot and every 3 days when cool. Water in the early morning.
What temperature does nemesia need?
It does best between 15 °C and 24 °C and survives from 0 °C to 30 °C. Seed needs soil above 18 °C to germinate, ideally around 21 °C.
Can I grow nemesia in winter?
Not outdoors anywhere that frosts — it is highly frost-sensitive and will not survive it. In a frost-free winter it grows slowly; anywhere colder, treat it as a warm-season crop.
How do I know when nemesia is ready to harvest?
Fully open flowers; Vibrant color. Once picked: use fresh for display; not typically stored.
How much does one nemesia plant produce?
Roughly 0.02 kg from a 20 litre container, or about 0.05 kg in open ground. Larger containers give proportionally more, up to a point.