Hydroponic Ludwigia: Red Stem Plants Grown in Jars of Water
A hydroponic ludwigia is a stem of Ludwigia set in a jar of water so it roots plus grows without soil. In water the stems reach for the surface plus the tips poke out into the air, often red in color.
The short answer
NC State Extension notes ludwigia is easy to grow from stem cuttings. Water purslane, Ludwigia palustris, forms rootlets near the lower leaf axils. Its stems are often red plus the leaves turn redder in sunlight. For hydroponic ludwigia, root stems in a jar in bright light plus trim them so they stay in the jar.
What is ludwigia?
NC State Extension describes Ludwigia as a genus that often grows in bogs, ponds plus lakes. Water purslane, Ludwigia palustris, is a mat forming perennial in the evening primrose family. Its stems are succulent plus often red. Out of water they creep along the ground up to two feet.
In water, NC State notes, the stems seek the surface plus the stem tips poke out. Leaves are about 1 1/2 inches long plus 3/4 inch across, medium green to dark reddish green.
UF/IFAS Extension notes some emergent plants are amphibious plus can grow fully out of water or fully submerged.
How do you root ludwigia stems?
NC State notes the genus is easy to grow from stem cuttings or seed. Water purslane has a shallow, fibrous root system. It makes new plants by forming rootlets near the axils of its lower leaves. Some species root at the nodes as they creep along the ground.
Cut a stem with several nodes, strip the lowest leaves plus stand it in a jar of water with the bare nodes under the surface.
| Item | What to know | Source |
|---|---|---|
| Rooting | Rootlets form near lower leaf axils | NC State |
| Stems | Succulent plus often red | NC State |
| Leaf color | Redder in sunlight | NC State |
| Leaf size | About 1 1/2 by 3/4 inch | NC State |
| Spread | Some species take over a pond quickly | NC State |
Source: NC State Extension.
Why do ludwigia leaves turn red?
NC State Extension notes water purslane leaves become more red when they get sunlight. Bright light yields the reddest tips. Low light leaves the plant greener.
NC State also notes some Ludwigia species can quickly take over a pond. Creeping water primrose, Ludwigia hexapetala, is listed as invasive. Grow ludwigia only in jars plus never put trimmings into ponds or streams.
How to: step by step
- Cut a stem with several leaf nodes.
- Strip the leaves from the lowest nodes.
- Stand the stem in a jar of water.
- Hold the bare nodes under the surface.
- Place the jar in bright light.
- Trim tips that grow past the jar.
Troubleshooting
Green leaves with no red: low light. NC State notes the leaves redden in sunlight. Move the jar somewhere brighter.
Stems lying flat: stems out of water spread along the ground. Sink the base so the tips rise.
Green film in the jar: extra nutrients. UF/IFAS notes high nutrient levels cause algae. Refill with low nutrient water.
For more on root media see hydroponic in different mediums plus caring for your hydroponic system. Read aquarium water for cannabis. Kind Seed Co also stocks cannabis seeds.
Sources
- Ludwigia palustris (marsh seedbox), NC State Extension Gardener Plant Toolbox
- Ludwigia (water primrose), NC State Extension Gardener Plant Toolbox
- Freshwater ornamental aquatic plant production in Florida (FA251), UF/IFAS Extension
- Water gardens: planting aquatic plants (PlantTalk 1026), Colorado State University Extension
FAQ
Can ludwigia grow without soil?
NC State Extension notes water purslane stems seek the surface when growing in water plus root from rootlets near the lower leaf axils. UF/IFAS Extension notes some emergent plants are amphibious plus can grow fully out of water or fully submerged.
How large are ludwigia leaves?
NC State Extension lists water purslane leaves at about 1 1/2 inches long plus 3/4 of an inch across. They are medium green to dark reddish green plus rubbery to the touch. Leaves sit opposite each other along the succulent stems.
Will ludwigia spread outdoors?
NC State Extension notes some Ludwigia species can quickly take over a pond. Creeping water primrose is listed as invasive. Stems of some species root at the nodes plus can grow up to 9 feet along the ground.
Does ludwigia need fertilizer in jars?
No source gives a rate for ludwigia. UF/IFAS Extension notes high nutrient levels in water cause algae blooms that block light plus take up nutrients. It advises low nutrient water plus avoiding overfertilization in aquatic plant systems.
Does ludwigia flower in water?
NC State Extension notes that when water purslane stems are above the water, small flowers form at the leaf axils from midsummer to fall. Other Ludwigia species have yellow flowers that open at dusk over a long bloom season.
