The garden
The complex is set in and around a large charbagh (a formal Mughal garden divided into four parts). Measuring 300 m × 300 m, the garden has sunken parterres or flowerbeds, raised pathways, avenues of trees, fountains, water courses, and pools that reflect the Taj.
Each of the four quarters of the garden is divided into 16 flowerbeds by raised pathways. A raised marble water tank at the center of the garden, halfway between the tomb and the gateway, reflects the Taj.
The charbagh garden was introduced to India by the first Mughal emperor Babur, a design inspired by Persian gardens. The charbagh is meant to reflect the gardens of Paradise (from the Persian paridaeza -- a walled garden). In mystic Islamic texts of the Mughal period, paradise as described as ideal garden, filled with abundance. Water plays a key role in these descriptions: In Paradise, these text say, four rivers source at a central spring or mountain, and separate the garden into north, west, south and east.
Walkways beside reflecting pool
Most Mughal charbaghs are rectangular in form, with a central tomb or pavillion in the center of the garden. The Taj garden is unusual in siting the main element, the tomb, at the end rather than at the center of the garden. But the existence of the newly discovered Mahtab Bagh or "Moonlight Garden" on the other side of the Yamuna provides a different interpretation -- that the Yamuna itself was incorporated into the garden's design, and was meant to be seen as one of the rivers of Paradise.
The layout of the garden, and its architectural features such as its fountains, brick and marble walkways, geometric brick-lined flowerbeds, and so on, are similar to Shalimar's, and suggest that the garden may have been designed by the same engineer, Ali Mardan.
Early accounts of the garden describe its profusion of vegetation, including roses, daffodils, and fruit trees in abundance. As the Mughal empire declined, the tending of the garden declined as well. When the British took over management of the Taj, they changed the landscaping to resemble more the formal lawns of England.