Perhaps you've inherited a vegetable garden or have forgotten what you planted and where. To identify the plants popping up in your garden, look for identifying features, such as the size, shape and colour of the leaves. When planting vegetables, group similar types together and use labelled sticks until you become familiar with each plant. To identify weeds versus vegetables, remember that weeds tend to grow haphazardly throughout the garden, while vegetables emerge in a more ordered style. When in doubt, leave the plant until it matures to a recognisable point.
Determine if the plant in question is a leafy green vegetable, a root vegetable or a fruiting vegetable. Leafy green vegetables produce leaves that come directly out of the ground. These plants typically remain under 30 cm in height unless they are allowed to go to seed, in which case they may grow around one metre high and produce flowers. Fruiting vegetables, on the other hand, produce leaves from stems and vines and may grow more than one metre high. Root vegetables usually have straight, vertical leaves. Potatoes are one exception to this rule.
Look at the colour and texture of the leafy green vegetables. Spinach has crinkled, dark green leaves, while lettuces have thinner, smooth leaves in a variety of colours. Kale also has thick, crinkled leaves and stems that may be white, red or orange. Vegetables in the cole family, such as cabbage and cauliflower, produce leaves close to the ground, followed by a single head developing in the centre of the plant. Broccoli produces multiple heads.
Examine the leaf shapes of fruiting vegetables. Tomatoes have deeply cut, slightly furry leaves and a characteristic tomato scent. Peppers have smooth, dark green, elongated leaves. The leaves of green beans are thick and heart-shaped. Also notice if the plant produces vines. Some (but not all) tomatoes, beans and snap peas produce vines. Peppers do not.
Examine the size of the leaves, as well as the plants. Cucurbits, including cucumbers, squash and pumpkins, produce some of the largest leaves in the garden, growing 7.5 to 20 cm wide. These leaves are heart-shaped, dark green and lobed or smooth.
Identify root vegetables. Carrots have fine, lacy foliage that emerge vertically from one small area. Onions and fennel produce straight, spear-like leaves that also grow vertically. Onion plants have an onion scent. Potatoes have an open, spreading form that resembles that of small tomato plants.