RootsHold the plant in the soil and take up water. A tomato also grows new roots from any part of the stem that is buried.
Main stemThe central stalk, covered in fine sticky hairs. Gardeners tie it to a stake.
LeafA tomato leaf is compound: one stalk with five to nine leaflets.
FlowerA small star-shaped flower with five points. Each one can become a tomato.
FruitThe tomato itself, which grows from a flower. To a botanist it is a berry.
LeafletOne of the small blades that make up a leaf. Its edge is toothed.
Flower clusterA branched stalk with several flowers. The tomatoes form here, in a bunch.
SuckerA new shoot that grows where a leaf meets the stem. Gardeners often pinch suckers off.
Growing tipThe top of the stem, where new growth is made.
Cut tomato 3
SeedsSmall flat seeds in the hollows of the fruit. One tomato can hold more than a hundred.
LoculeA hollow in the fruit, full of seeds. Small tomatoes have two; big ones have many.
Fruit wall (pericarp)The fleshy wall of the fruit. Botanists call it the pericarp.
How this list was compiled: Every name checked on 2026-10-01 in at least two of these. (1) Wikipedia, English edition, Tomato, https://en.wikipedia.org/wiki/Tomato (branching stems whose tip has a terminal bud that does the growing; leaves with five to nine leaflets on petioles, toothed; stems and leaves densely hairy; yellow five-pointed flowers in clusters of three to twelve; the fruit a berry whose flesh is the pericarp walls, with locules full of seeds, two in some small kinds and many in the largest; hairs on the vine turn into roots where it touches moist ground). (2) North Carolina State Extension, Plant Toolbox, Solanum lycopersicum, https://plants.ces.ncsu.edu/plants/solanum-lycopersicum/ (stems with sticky, dense hairs; compound leaves with 5 to 9 toothed leaflets; small yellow starry five-lobed flowers; the fruit a berry that may hold over 100 seeds; extra roots on any buried part of the stem). (3) University of New Hampshire Extension, Pruning Tomato Plants, https://extension.unh.edu/resource/pruning-tomato-plants-fact-sheet (suckers, the new shoots that grow in the leaf axils; flower clusters; leaders; stakes; the terminal bud). (4) Rutgers New Jersey Agricultural Experiment Station, FS678, https://njaes.rutgers.edu/fs678/ (sucker shoots between leaf stem and main stem; flower clusters; staking). (5) University of Florida IFAS, Gardening Solutions, Tomatoes, https://gardeningsolutions.ifas.ufl.edu/plants/edibles/vegetables/tomatoes/ (suckering, main stems, stakes, fruit clusters). (6) North Carolina Extension Gardener Handbook, chapter 16, https://content.ces.ncsu.edu/extension-gardener-handbook/16-vegetable-gardening (adventitious roots all along the stem). (7) University of Minnesota Extension, Growing tomatoes, https://extension.umn.edu/vegetables/growing-tomatoes (the top or terminal growing point; new roots from the buried part of the stem). (8) United States Department of Agriculture: Agricultural Marketing Service, Tomatoes, Shipping Point and Market Inspection Instructions, https://www.ams.usda.gov/sites/default/files/media/Tomato_Inspection_Instructions%5B1%5D.pdf, and Agriculture Handbook 66, https://www.ars.usda.gov/arsuserfiles/oc/np/commercialstorage/commercialstorage.pdf (walls, locules, seed cavities and seeds; outer pericarp). Detail lines are in our own words. Licence: own work
The drawing: Drawn for this site on 2026-10-01 from plain geometry; nothing traced. Licence: own work
How it works
The parts of a tomato plant are its roots, a main stem, leaves made of leaflets, clusters of flowers and the fruit. The second drawing shows the parts of a tomato cut across: the wall, the hollows and the seeds.
Read the full guide
The plant first, then inside the fruit
Numbers 1 to 5 are the parts every plant has: the roots, the main stem, a leaf, a flower and the fruit. Numbers 6 to 9 are closer looks: one leaflet, a flower cluster, a sucker in the angle between a leaf and the stem, and the growing tip. Numbers 10 to 12 are in the cut tomato: the seeds, a locule and the fruit wall.
A leaf is the whole stalk with all its blades. A leaflet is one of the blades.
To find a sucker, look where a leaf meets the stem: the small shoot between the two is one.
Questions and answers
What is a sucker on a tomato plant?
A new shoot that grows in the angle between a leaf and the main stem. Left alone it becomes another stem with its own leaves and flowers. Gardeners who stake their plants often snap suckers off while they are small.
Is a tomato a fruit or a vegetable?
To a botanist it is a fruit, and a berry: it grows from the flower and holds the seeds. In the kitchen it is treated as a vegetable.
What is inside a tomato?
A fleshy wall, and hollows called locules that are full of seeds. Some small tomatoes have two locules, round ones usually three to five, and the largest kinds have many small ones.
Why do gardeners bury part of a tomato stem?
Because a tomato can grow roots from its stem. Any part of the stem that is under the soil sends out new roots, so a plant set deep ends up with more of them.