Types and features of fruit plants
Fruit plants come in three shapes.
- Trees with one trunk: apple, mango, orange.
- Vines that climb a support: grape, kiwi.
- Shrubs with many thin stems: blueberry, currant.
By leaf habit there are two groups. Deciduous trees (apple, peach, grape) drop leaves in the cold season and rest. Evergreen trees (mango, citrus, banana) keep leaves all year. Fruits are also grouped by climate: temperate (apple, pear), subtropical (citrus) and tropical (mango, banana).
Growth and the yearly cycle
A deciduous fruit tree follows one cycle each year: dormancy (winter rest) → bud break and flowering (spring) → pollination and fruit set → fruit growth (summer) → ripening and harvest (autumn) → leaf fall. Flower buds for next year are made during the summer, so how we treat the tree this year decides the crop next year. Fruit tree wood is perennial, which means the same tree lives and fruits for many years.
Leaves make sugar by photosynthesis and send it to the fruits. More healthy leaves per fruit means sweeter fruit.
Environment and growth control
Growth depends on temperature, light, water, wind and soil.
- Chilling: many temperate fruits need a number of cold hours in winter. Without it, buds open late and unevenly.
- Frost in spring can kill flowers. Growers use windbreaks, smoke or water spray to protect them.
- Light: sun on the leaves makes sugar and colour in the fruit.
- Water and soil: deep, well-drained soil and steady water are best. Waterlogging rots roots.
Growers control growth by pruning (cutting branches to shape the tree and let in light), thinning (removing extra fruits so the rest grow big), training on supports, and giving water and nutrients on time.
Breeding and propagation
Breeding makes new varieties by crossing parents with good traits (sweet, disease resistant, big, long storage) and choosing the best seedlings. It takes many years for trees.
Propagation means making more plants. A seedling from a seed is not the same as its parent, so growers copy a good tree in other ways: cuttings (a piece of stem makes roots), layering (a bent branch roots while joined), and grafting. In grafting the scion (a twig of the good variety) is joined to the rootstock (a strong root with the lower stem). Their cut cambium layers must touch so they grow together; the joint is tied with tape. The rootstock can give disease resistance and control tree size.
Try it
1) In the 3D press the three buttons and count the fruits in the tree. 2) Move to Autumn, count, then press Prune and count again. Are the fruits fewer or bigger? 3) At home, plant an apple or mango seed and a cutting of guava or rose. Note which gives a copy of the parent. 4) Press Graft in the 3D and watch the scion come down.
Key formulas and definitions
- Yearly cycle: rest → flower → fruit set → grow → ripen → leaf fall
- Graft = scion (top, good fruit) + rootstock (root, strong)
- Pruning: fewer fruits, bigger fruits, more light
- Propagation: cuttings, layering, grafting (copies); breeding (new variety)
Worked examples
1. A tree makes 200 fruits of 100 g each. After thinning it keeps 125 fruits of 150 g each. Compare total weights.
Before: 200 × 100 = 20000 g. After: 125 × 150 = 18750 g. Total is slightly lower, but the fruit is bigger and often sells at a higher price.
2. Why will an apple seed not give the same apple as its parent?
A seed comes from pollination, which mixes traits of two parents, so the seedling is different. Grafting copies the parent exactly.
3. A grower wants a small tree that is easy to pick and resists root disease. Which part of the graft should he choose carefully?
The rootstock. It controls tree size and root disease resistance, while the scion gives the fruit.
Common mistakes
- Calling every leafless winter tree dead. Deciduous trees are only resting.
- Mixing up scion and rootstock. The scion is the top twig; the rootstock is the root part.
- Pruning hard in the wrong season, which can remove next year's flower buds.
- Thinking more fruit per tree is always better. Too many fruits stay small and sour.