Two plants can look equally good in a shop and do very differently in your home. The difference is usually the spot, not the plant. This page sets out four checks to make before you choose between two houseplants: light, water, size and pets. Then it lists every comparison we have published.
1. Light: measure the spot first
Light is the check that rules out the most plants. University of Illinois Extension calls light one of the most limiting factors for houseplants. It says most plants perform best in bright light, while some tolerate moderate to low light.
Illinois gives these levels, with typical window positions. We have converted foot-candles to lux.
| Light level (Illinois) | Intensity | Typical position |
|---|---|---|
| Low | About 800 lux (75 foot-candles) | A few feet from a north window; 1–3 m (3–10 ft) from an east or west window; 4.5–6 m (15–20 ft) from a south window |
| Medium | About 1,600 lux (150 foot-candles) | Directly in front of a north window; a few feet from an east or west window; 1–3 m (3–10 ft) from a south window |
| Bright | About 3,200 lux (300 foot-candles) | Directly in front of an east or west window; up to 1.5 m (5 ft) from a south window |
| Direct | About 16,000 lux (1,500 foot-candles) | Directly in front of a south window |
Illinois also lists minimum light for common houseplants. Heartleaf philodendron, snake plant and peace lily are in its low-light group. Pothos and spider plant are in the medium group. English ivy, jade plant and weeping fig need bright light. A low-light plant still needs light: the low level is a minimum, not a preference.
Light changes through the year. Illinois notes that the sun’s angle shifts with the seasons, and that trees outside block more light in summer than after their leaves fall. Check the spot in more than one season if you can. Our light requirements chart lists more plants.
Comparing grow lights
If the spot is too dark, a grow light changes the choice. Illinois says cool white fluorescent bulbs work well for foliage plants. For flowering plants it suggests incandescent or special grow-light bulbs, because flowering also needs infrared light. It suggests 14–16 hours of light a day in low light, and no more than 16 hours, because plants need a rest period.
For LED, fluorescent and other lamp types compared, see grow lights compared, grow light distance and duration, grow lights for low-light apartments and African violet grow lights: LED vs fluorescent.
2. Water: match the plant to your habits
University of Illinois Extension says watering on a schedule usually does not work. Plant type, temperature, humidity, light, pot size, plant size, potting mix and drainage all change how fast a pot dries. It recommends testing the soil with a finger to about 5 cm (2 in) deep.
Plant descriptions usually fall into three groups (Illinois):
- Constantly moist but not soggy.
- Allowed to dry moderately between waterings.
- Very slightly moist at all times.
The pot matters as much as the plant. Virginia Cooperative Extension explains that terracotta dries faster than plastic or glazed pots. Small pots dry faster than large ones, and a pot that is too large leaves roots in a mix that stays too wet.
If you often forget to water, Iowa State’s criteria help. Its easy-plant list favours plants that thrive despite inconsistent watering and tolerate dry soil and low humidity.
3. Size and growth habit
Check the mature size, not the size in the shop. NC State’s Plant Toolbox gives dimensions for each plant. A spider plant grows to about 30–45 cm (1–1.5 ft) tall and 30–60 cm (1–2 ft) wide. Pothos vines can reach 12 m (40 ft).
Habit matters too. A trailing vine needs a shelf, a hanging basket or a support. A clumping plant needs width. A climber needs a pole.
4. Pets
If a cat or dog chews plants, check this before anything else. Look up the botanical name in the ASPCA toxic and non-toxic plants database. The ASPCA warns that plants can look different from its photos, so check the name, not the picture. It also notes that any plant material can cause vomiting and stomach upset in pets. Plants listed as non-toxic are not expected to be life-threatening.
Our pet-safe plants guide and toxic plants guide sort common houseplants by both lists.
Plant comparisons
| Comparison | What decides it | Guide |
|---|---|---|
| Snake plant vs ZZ plant | Leaf shape, direct sun, winter watering | Snake plant vs ZZ plant |
| Pothos vs heartleaf philodendron | Leaf stalk, light minimum, watering | Pothos vs philodendron |
| Pothos cultivars | Variegation, light, true vs look-alike “pothos” | Pothos varieties compared |
| Philodendron types | Climbing vs self-heading habit, size | Philodendron varieties |
| Spider plant vs pothos | Pet safety, fluoride sensitivity, plantlets vs cuttings | Spider plant vs pothos |
| Monstera deliciosa vs adansonii | Leaf splits vs oval holes, size | Monstera deliciosa vs adansonii |
| Peace lily vs snake plant | Opposite watering, light for flowering | Peace lily vs snake plant |
| Philodendron vs snake plant | Watering habit, trailing vs upright | Philodendron vs snake plant |
| Philodendron vs rubber plant | Vine vs tree form, light | Philodendron vs rubber plant |
| Dracaena vs Chinese evergreen | Light, cold sensitivity, fluoride | Dracaena vs Chinese evergreen |
| Calathea vs maranta | Naming, leaf pattern, humidity | Calathea vs maranta |
| Aloe arborescens vs aloe vera | Growth habit, leaf shape, uses | Aloe arborescens vs aloe vera |
| ZZ plant vs money tree | Low light, watering habit, pet safety | ZZ plant vs money tree |
| Strelitzia reginae vs nicolai | Flower colour, eventual size, indoor space | Strelitzia reginae vs nicolai |
For a short list matched to the light you have, see plants for dark rooms, small plants for desks and shelves, large floor plants, office plants and easy plants for beginners.
Pots, mix and problem comparisons
| Comparison | What decides it | Guide |
|---|---|---|
| Terracotta vs plastic pots | Drying speed, weight, salts | Terracotta vs plastic pots |
| Potting mix vs compost or garden soil | Drainage and air in a container | Potting soil vs compost |
| LECA vs potting mix | Water holding, salts, root air | LECA vs soil |
| Neem oil vs insecticidal soap | How each kills, heat limits, sensitive plants | Neem oil vs insecticidal soap |
| Overwatered vs underwatered | Wet or dry mix, root condition | Overwatered or underwatered? |
| Soft vs wrinkled cactus | Rot, thirst or cold | Cactus soft or wrinkled |
| Thirsty Monstera vs wet root zone | Mix moisture and roots | Monstera watering |
How to use a comparison
Start with the spot. Measure or estimate its light using the table above, then rule out any plant whose minimum is higher. Next, rule out plants that are toxic to your pets. Choose between what remains by size and by how often you will realistically water.
After buying, check each pot on its own rather than watering everything on one day.
References
- University of Illinois Extension: Houseplants: Lighting
- University of Illinois Extension: Houseplants: Watering
- Iowa State University Extension and Outreach, A. Steil: Easy low-maintenance houseplants
- Virginia Cooperative Extension, K. S. Criscione and A. Holliday-Goulart: Properly Watering Container Houseplants, SPES-804P
- NC State Extension Gardener Plant Toolbox: Epipremnum aureum
- NC State Extension Gardener Plant Toolbox: Chlorophytum comosum
- ASPCA Animal Poison Control Center: Toxic and Non-Toxic Plants List