Arrowhead Plant Leaves Turning Yellow: Water Plus Light
Arrowhead plant leaves turning yellow call for a check of watering plus light first. NC State Extension notes that syngonium likes a warm, humid spot plus moist soil out of full sun. University of Missouri IPM adds that improper watering is a common cause of houseplant leaf problems.
The short answer
Start with the soil. University of Missouri IPM notes that more houseplants are killed from overwatering than from any other cause, yet plants should not get too dry either. NC State Extension advises a warm, humid spot out of full sun. Iowa State University Extension suggests grow lights on for 14 hours a day.
Is watering the cause?
University of Missouri IPM notes that more houseplants are killed from overwatering than from any other cause. Do not allow houseplants to become too dry either, the same source advises.
As a potting mix dries, it loses water but not the salts in the soil solution, University of Missouri IPM explains. Salinity in the root zone then rises.
NC State Extension lists moist soil drainage for syngonium. The same page notes that bacterial leaf spots plus soft rot can occur.
Is the light right?
NC State Extension advises avoiding locations with full sun, as direct sunlight will tend to burn or bleach the foliage. Bright yet shaded spots suit the plant.
University of Illinois Extension notes that both the amount plus the quality of light matter. Indoors, only a small amount of the outdoor light enters the room.
In low light conditions, plants can benefit from increasing the duration of light, the same source notes. Light duration is the number of hours of light a plant gets in 24 hours.
| Cause to check | What to look for | Source note |
|---|---|---|
| Overwatering | Soggy potting mix | Let the mix dry somewhat |
| Too dry | Dry mix plus salt buildup | Do not let it get too dry |
| Direct sun | Burned or bleached leaves | Avoid full sun |
| Low light | Dim room in winter | Add a lamp for 14 hours |
Source: NC State Extension plus Iowa State University Extension.
How do grow lights help?
Iowa State University Extension notes that light is often the most limiting growth factor for houseplants. Nearly all indoor plants would benefit from some supplemental lighting during winter.
The same source suggests installing an LED or fluorescent grow light as directed plus leaving it on for 14 hours a day. Fluorescent fixtures should sit 6 to 12 inches from the foliage.
Iowa State University Extension adds that LED fixtures can be 12 to 24 inches away in most cases. Fixtures on a chain can move closer to or farther from the plants.
How to: step by step
- Touch the potting mix before watering.
- Avoid soggy mix plus avoid letting it dry out fully.
- Flush the mix with clear water if a white residue appears.
- Shift the plant out of direct sun.
- Add a grow light for 14 hours a day in a dim room.
- Repot every few years.
Troubleshooting
Soggy mix plus yellowing: overwatering. Water less often.
Bleached leaves: direct sun. Move to bright shade.
White crust on the mix: salt buildup. Flush with clear water.
For related reading see a guide to overwatering and cannabis growth, optimal lighting for growing indoors plus potting up cannabis seedlings. Kind Seed Co also stocks cannabis seeds.
Sources
- Syngonium podophyllum (arrowhead vine), NC State Extension Gardener Plant Toolbox
- Lighting, houseplants, Illinois Extension
- How to set up supplemental lights for indoor plants, Iowa State University Extension
- Leaf tipburn on houseplants, University of Missouri IPM
FAQ
How much light does an arrowhead plant need?
NC State Extension advises avoiding full sun, since direct sunlight tends to burn or bleach the foliage. Bright but shady spots suit it. In dim rooms, Iowa State University Extension suggests a grow light on for 14 hours a day, especially in winter.
Does an arrowhead plant need repotting?
NC State Extension notes that repotting every few years plus trimming the root system can make the plant easier to manage. Young plants have a shrubby habit, but older plants take on a vine like habit. The same page lists an available planting space of 12 inches to 3 feet.
Why is there white crust on the soil?
University of Missouri IPM notes that a whitish residue on top of the growing medium means the medium should be flushed with clear water. It also advises never watering houseplants with water that has passed through a water softener. Salt buildup can mimic other watering problems.
How far should a grow light be from the leaves?
Iowa State University Extension notes that fluorescent fixtures should sit 6 to 12 inches from the foliage. LED fixtures can be 12 to 24 inches away in most cases. Distance from fixture to foliage can change the light the plant receives in a significant way.
Does an arrowhead plant like humidity?
Yes. NC State Extension notes that the ideal location for syngonium includes a warm setting with high humidity. The same page lists moist soil drainage. Bacterial leaf spots plus soft rot can occur, the same source notes, so avoid soggy potting mix.
