All tea, whether green, black, oolong, or white, comes from a single plant species: Camellia sinensis. It’s an evergreen shrub that, left unpruned, can grow into a small tree. Commercial tea farms keep the plants trimmed to waist height, harvesting only the youngest leaves and buds at the tips of each branch. The journey from seed or cutting to a harvestable bush takes about five years, and a well-maintained plant can keep producing for decades.
The Tea Plant: Two Main Varieties
There are two major varieties of tea plant, and they look quite different. The Chinese variety (var. sinensis) has small leaves, typically 2 to 3 inches long, and tolerates cooler climates well. The Indian variety (var. assamica), originally from the Assam region, produces larger leaves of 3 to 5 inches and prefers warmer, more tropical conditions. Most of the world’s tea gardens grow one of these two varieties or hybrids bred from them.
The Chinese variety tends to be used for delicate green and white teas, while the larger-leafed Assam variety is the backbone of bold black teas. But the distinction isn’t rigid. Processing method, not just plant variety, determines what ends up in your cup.
Climate and Soil Conditions
Tea is particular about where it grows. The optimal temperature range is 18 to 23°C (roughly 64 to 73°F), with annual rainfall between 1,500 and 2,000 millimeters (about 59 to 79 inches). Relative humidity should stay around 80 to 85 percent. This is why the world’s great tea regions cluster in subtropical and tropical zones with abundant rain: southern China, northeast India, Sri Lanka, Kenya, and Japan.
Soil chemistry matters just as much as weather. Tea plants actively prefer acidic soil with a pH between 4.0 and 5.5, which is far more acidic than what most crops can tolerate. In fact, tea is unusual among cultivated plants because soil acidity doesn’t just fail to harm it; the plant thrives in those conditions. At low pH, aluminum in the soil becomes soluble, and tea plants have evolved to handle it. Nitrogen is the nutrient the plant demands most, followed by potassium, calcium, phosphorus, sulfur, and magnesium.
Starting a Tea Plant
Tea can be grown from seed, but commercial farms almost always use stem cuttings instead. A plant grown from seed can vary unpredictably from its parent, producing leaves with different flavor or yield. A cutting, by contrast, is a genetic clone of the mother plant, so growers can maintain consistent quality across thousands of bushes.
The process starts with selecting a healthy mother plant. Growers let new shoots grow until the tip goes dormant and the stem hardens. They then take single-node cuttings, each with one leaf and about 1.5 inches of woody stem. The cut end gets dipped in a rooting hormone and pushed into a well-drained growing medium like perlite or vermiculite, kept at a pH below 5.0. The cuttings root under heavy shade (80 to 90 percent) and constant misting so they never dry out. Roots develop within three to four months, and after transplanting into pots, the young plant is typically ready for the field about a year after the cutting was first taken.
From Seedling to First Harvest
Once in the ground, a tea plant needs roughly five years before it’s ready for regular leaf harvesting. During those early years, the bush is building its root system and developing the woody framework that will support decades of leaf production. Growers apply slow-release fertilizer monthly from late spring through late summer once harvesting begins.
The goal during this establishment phase is to shape the bush into what’s called a plucking table: a flat, dense canopy of branches at a convenient height for picking. For hand harvesting, the plucking table is maintained between 60 and 100 centimeters (about 2 to 3.3 feet) above the ground. This flat surface maximizes the number of new shoot tips that sprout upward, giving harvesters more to pick.
Seasonal Growth and Flushing
Tea plants don’t produce leaves at a steady rate year-round. Growth happens in cycles called flushes. After a period of dormancy or rest, the plant sends out a burst of new shoots with tender young leaves. These are what get harvested.
In most tea-growing regions, the cycle follows a seasonal pattern. Winter dormancy lasts from roughly November through February, when the plant rests and produces little or no new growth. The spring harvest from March through May is the most prized season, especially for green teas, because the leaves have had months to accumulate flavor compounds during dormancy. Summer harvests from June through August produce faster growth due to heat, but the leaves tend to have a different chemical balance. Some regions get a third or even fourth flush in autumn, though yields taper off as the plant prepares for winter rest again.
In tropical climates near the equator, like parts of Kenya and Sri Lanka, there’s no true winter. Tea plants in these regions can flush year-round, producing harvestable leaves every one to two weeks depending on rainfall and temperature.
Pruning for Productivity
Left alone, a tea plant would grow into a tree 30 feet tall or more. Pruning keeps it as a low, bushy shrub optimized for leaf production. Maintenance pruning happens every two to four years, cutting back the top of the bush to remove old, woody stems and stimulate fresh growth from below. With each pruning cycle, the plucking table rises about 2 to 3 centimeters, or roughly 10 centimeters per year over the full cycle.
After a prune, the bush needs time to regrow before harvesting can resume. New shoots are “tipped” once they reach a set height, usually about 60 centimeters above the ground, to encourage lateral branching and rebuild the plucking table. This recovery period is a deliberate investment: sacrificing a few months of harvest to keep the plant productive for years to come.
How Shade Changes the Leaves
Some of the most valued teas in the world, including matcha and gyokuro, come from plants that are deliberately shaded before harvest. Blocking sunlight triggers measurable changes in leaf chemistry.
When tea plants receive less light, they produce significantly more chlorophyll to compensate, which is why shaded tea leaves turn a deeper, more vivid green. Plants shaded at about 85 percent (meaning only 15 percent of sunlight gets through) showed chlorophyll levels 1.3 to 1.4 times higher than unshaded plants. At the same time, shading boosts amino acid content, particularly theanine, the compound responsible for the savory, sweet character of high-quality green tea. Caffeine also increases under shade.
The tradeoff is that shading decreases polyphenols, especially catechins, which are the compounds that give tea its astringent, bitter edge. This is why shaded teas like matcha taste smoother and sweeter than sun-grown teas. Moderate shading produces the best results; too much shade actually reverses the amino acid gains.
Altitude and Flavor
Tea grown at high elevations is often marketed as premium, and the environment does change the plant in real ways. Cooler temperatures, stronger UV exposure, and greater temperature swings between day and night all slow the plant’s growth rate. Slower growth generally concentrates certain flavor compounds in the leaves.
Interestingly, research shows that both catechins and caffeine accumulate less at the highest altitudes. Theanine content also tends to decrease with elevation, which complicates the simple “higher is better” narrative. The flavor differences in high-altitude teas likely come from a complex interaction of soil, microclimate, cloud cover, and the stress the plant experiences, not from a single compound being dialed up or down.
What Gets Picked
Only the very tip of each growing shoot is harvested: typically the bud and the top two or three young leaves. This “two leaves and a bud” standard is the foundation of quality tea production worldwide. Older, larger leaves lower on the stem contain less of the flavor compounds that make tea worth drinking.
Hand plucking allows pickers to select only shoots at the right stage of growth, which is why it remains the standard for premium teas. Machine harvesting is faster and cheaper but less selective, often shearing the top of the plucking table and collecting a mix of young and older leaf material. The harvested leaves are still just raw material at this point. Whether they become green, black, white, or oolong tea depends entirely on what happens next during processing: how much the leaves are allowed to oxidize before being dried.