One of these will die if you water it like the other. That's the first thing to know about choosing between Chinese elm and jade for a bright windowsill, because both get sold as indoor beginner bonsai and their care instructions are close to opposite.
Chinese elm (Ulmus parvifolia) is a thirsty deciduous tree that wants the top quarter-inch of soil to dry and then a full drink, every 2 to 3 days indoors in summer. Jade (Crassula ovata) is a succulent that wants bone-dry soil, a soak, and then 7 to 10 days of nothing. Water the jade on the elm's schedule and the trunk rots from the soil line up. Water the elm on the jade's schedule and it wilts flat every week.
Match the tree to your habits, not the other way around. Check on plants daily? Elm. Check on them when you remember? Jade.
| Attribute | Chinese Elm | Jade |
|---|---|---|
| Difficulty | Beginner | Beginner |
| Environment | Indoor or outdoor | Indoor, outside in summer |
| Light | Bright window to full sun | Bright direct, 4-6 hours |
| Water | Every 2-3 days indoors | Let dry, every 7-10 days |
| Growth Rate | Fast | Slow |
| Mature Size | 10-20 inches | 8-16 inches |
| Best Styles | Broom, informal upright | Informal upright, slanting |
| Price Range | $20-60 starter | $15-50 starter |
Watering rhythm is the whole decision. A Chinese elm indoors wants a drink every 2 to 3 days in summer, whenever the top quarter-inch feels dry, and it tells you loudly when you miss: the leaves wilt flat, then stand back up within hours of a soak. Jade wants the soil dry two inches down before you water, which means every 7 to 10 days in summer and every 2 to 3 weeks in winter. Jade doesn't wilt when thirsty; the leaves wrinkle. And it doesn't recover from too much water the way an elm recovers from too little. Overwatering kills more jade than everything else combined.
Light tilts toward the jade. Both want a bright window. The elm grows in a south or west window at about a third of its outdoor pace, with bigger leaves, and declines slowly near a north window. Jade wants 4 to 6 hours of direct sun and stretches into a stick without it, but it's fine in dry heated air that invites spider mites onto an elm.
What you build is different. On an elm you build a canopy: cut shoots from 6 to 8 leaves back to 2, and by fall each tip has become eight, with leaves down to half an inch by the second season. On a jade you build a trunk. The succulent tissue swells, and a pencil-thick cutting can carry a 2-inch trunk in four or five years. The elm reads as a tree because of its twigging; the jade because of its girth.
Same tools, different rules. Both are clip-and-grow species. The elm can be cut any time of year and closes small wounds within a season. Jade cuts have to land at a node, the wound needs 24 hours to dry before you water, and hard pruning waits for April or May. Wire is an elm technique only: elm branches bend and set in 3 to 6 months, while any jade branch thicker than a pencil snaps.
Temperature floors are far apart. An elm can summer outdoors and handle a cold winter, with the pot protected below about 25°F. Jade lives in a 50 to 85°F band and goes outside only once nights stay above 50°F, after a week in shade to avoid sunburn. Below 50°F it suffers.
Cost is small either way; pet safety isn't. A 4-inch jade is $5 to 8 at any garden center, a 6-inch $10 to 15, and the fattest trunk on the shelf is the one to buy. Nursery elm in a 1-gallon pot runs $15 to 30. Chinese elm is safe for cats and dogs. Jade is toxic to both, which settles it in many households.
Pick the Chinese elm if you want to practice bonsai: wiring, defoliation, building a canopy that fills in over two or three seasons. It's also the pick if you'll be home to water it, and if there's a cat or dog in the house.
Pick the jade if you travel, forget plants for weeks, or have a hot, dry, sunny room. It won't teach you much about wire, but it'll still be alive after a two-week trip, and the trunk gets fatter every year. If your only window faces north, don't buy either; neither tolerates dim light, and a grow light costs less than a replacement tree.
