Fruits

Seeds are contained within fruits which provide protection for the developing embryo and, often, a means of dispersal. Fruits can be sorted into two main categories; true fruits and false fruits. True fruits are formed from the ovary wall after fertilisation, while false fruits are formed from other parts of the flower other than, or as well as, the ovary wall. Within these two categories there are many different types of fruit:

True fruits

Dehiscent (seeds released into the air while fruit remains on parent plant) fruits

Capsule

These are often rounded fruits formed from a superior or inferior ovary (superior growing above the other flower parts, inferior growing under them, inset into the receptacle). Capsules shed seeds in different ways; same split down their length to release seeds, while others have holes near the top of the capsule through which seeds exit.

Examples of capsules:

• Poppy fruit (eg Papaver somniferum)
• Pink (Dianthus spp.) fruit
• Primrose (Primula spp.) fruit
• Evening Primrose (Oenothera spp.) fruit
• Violet fruit
• Lily fruit
• Foxglove (Digitalis spp.)

Siliqua

A pod-like structure which has a central portion with the seeds attached to it and two sides fitted to it which split off so the seeds can fall from the central portion.

Examples of siliquas:

• Mustard fruits (eg Brassica rapa)
• Wallflower (Erysimum cheiri)
• Cabbage (Brassica olearacea)
• Honesty (Lunaria annua)

Legume

A single pod-like structure which splits down both sides to release the seeds.

Examples of legumes:

• Lupin fruit (Lupinus spp.)
• Pea pods (Pisum sativum)
• Sweet pea (Lathyrus odoratus)
• Peanuts
• Wisteria fruit

Follicle

A single pod-like structure which splits down one side at maturity to release the seeds.

Exampes of follicles:

• Monkshood fruit
• Milkweed fruit (Aclepias spp.)
• Magnolias
• Columbines (Aquilegia spp.)

Indehiscent (seed remains in fruit after it has been shed from parent plant) succulent (juicy) fruits

Drupe

A drupe usually contains one seed only and the inner layer of the fruit is hardened and adheres tightly to the seed. The outer layers of the fruit are usually fleshy, although in the case of coconuts, for example, they are fibrous.

Examples of drupes:

• Sloe fruit
• Peaches
• Cherries
• Coconuts
• Olives
• Plums
• Raspberry (this is a group or ‘aggregation’ of drupes)
• Blackberry (this is a group or ‘aggregation’ of drupes)

Berry

Generally a berry contains many seeds and is fleshy throughout.

Examples of berries:

• Viburnum fruit
• Tomatoes
• Dates
• Grapes
• Kiwi
• Coffee

Pepo

These are berres where the skin is slightly hardened.

Examples of pepos:

• Cucumbers
• Courgettes

Hesperidium

Berries with a thickened skin (called a rind).

Examples of hesperidiums

• Lemons
• Limes
• Oranges

Multiple fruits

These are fleshy fruits which are derived from more than one flower, where the ovaries of the flowers have been squeezed together as they grew to form one fruit. There are three types of multiple fruits:

• Sorosis – eg Mulberry (Morus) fruit
• Syngonium – eg Figs (Ficus)
• Coenocarpium – eg Pineapples (Ananas)

Indehiscent dry fruits

Achene

These are single seeded fruits which are hardened to protect the seed. The majority of nuts are actually achene fruits. Some of the fruit we have listed here as achenes are, technically, cypselas because they have a stony fruit wall and are derived from a compound ovary. But that’s a bit too much detail for us!

Examples of achenes:

• Acorns (oak fruit)
• Buttercup fruit
• Hazelnuts
• Dandelion (this fruit also has a modified calyx attached to it to form a plume-like structure to help it float and be distributed by the wind)
• Strawberries (see also ‘pseudocarp’ below)
• Sunflower (Helianthus annuus)
• Clematis (Clematis spp.)
• Coreopsis (Coreopsis spp.)
• Dahlia (Dahlia spp.)
• Marigold (Calendula spp.)
• Zinnia (Zinnia spp.)
• Chestnut (Castanea sativa)

Samara

These are winged achenes, enabling the fruit to be carried by the wind. Some of these are, technically, schizocarp since they are divided into two or more one-seeded parts (eg maple fruits have two fruits with one seed each, each fruit has one ‘wing’ and they are stuck together to form a two winged device).

Examples of samaras:

• Elm fruit (Ulnus spp.)
• Ash fruit (Fraxinus spp.)
• Maple fruit (Acer spp.)

Caryopsis

These are grains; fruit where the seed coat is fused to the wall of the fruit.

Examples of caryopsis:

• Grasses, eg wheat, rice, barley
• Sweetcorn (Zea mays)

False fruits

Some fruits develop without seeds, these are known as parthenocarpic fruits. Cultivated strains of bananas, grapes and cucumbers are generally parthenocarpic (seedless).

Pomes

Pomes are derived from ovaries which are ‘inferior’, that is to say that they are positioned below the other parts of the flower (inset into the receptacle). The fruit comes from the inferior ovary plus a swollen receptacle area and/or other parts of the perianth. In apples, for example, the central ‘core’ (which contains the seeds) is the remains of the ovary, the main part of the flesh is actually the swollen receptacle.

Examples of pomes:

• Apples (Malus domestica)
• Pears (Pyrus spp.)

Pseudocarp

These are fruits where the ‘bulk’ of what appears to be the fruit is actually an accessory to the true fruit.

Example of a pseudocarp:

• Strawberries (the real fruits are the achenes stuck on the outside of the false fruit)
• Rose hips (the real fruits are the achenes within the fruit)

Apples and pears may also be considered to be pseudocarps.