Gardening Facts and Tips

Fastest Growing Vegetables Guide - Growth Rate Charts, Early Yield Tips

If you are starting a new vegetable garden or replanting one after the end of Winter it is useful to know which vegetables will provide quick yields. Some plants such as radishes reach maturity within 20-30 days and can be fully harvested after this period. Other plants be trimmed to provide leaves and shoots on the way to the plant reaching maturity.

Turnips are a good example of this. Leaves can be harvested from the tops after about 25 days which the turnip roots or tubers are still growing. Of course, you need to take care not to take too many leaves as this may affect the growth rate of the tubers.

The same applies for bulb onions which may take months to fully mature. But you can start harvesting the greens within 25-30 days and the plants will continue to develop the bulb and to and produce more more shoots.

Or you may want top grow scallions and harvest the entire plants which mature within 20-30 days.

This article includes a chart of the days to maturity of common vegetables, lists vegetable that can be harvested early for leaves and shoots and provides tips and guides for getting early yields from vegetables.

Discover the best time to grow vegetables in your growing zone.

Vegetable Growing in Space

NASA is testing a small portable greenhouse ('pillow') to grow fast growing lettuces at the International Space Station (ISS). This is a first and the leaves grown will not be eaten, but will be transported back to earth for testing. It is expected that plants will grow well in space once the problems of water-logging are addressed.

The absence of gravity, means that soil in a pot would float away. So soil is packed in a mesh bag to keep it together. NASA calls these bags "plant pillows". The other problem is watering the plants as the lack of gravity means that water pools around the roots and cannot drain away. Various pumps and other devices have been developed. Wicks in the 'pillows' deliver water to the plants and stop it pooling.

It is expected that the lack of gravity will not be a problem and that once the seeds germinate, the shoots are expected to grow towards the light. Growing food and crops will be an essential requirement on long manned trips to Mars.

Fastest Growing Vegetables - Harvesting Shoots and Leaves

The table below lists the time for maturity of common vegetables with the quickest shown first.

Plants from which leaves and shoots can be picked while the main product is still maturing have been labeled.

Brief notes about over-wintering and ways to speed up the initial yield have been provided.

There are broadly three groups of vegetables:

Fast Growing Vegetables - Plants that yield Leaves and shoots or a fully mature within 25 days.

• Spring Onion
• Arugula and other Salad Greens
• Green Onion – Scallions
• Radish - Spring
• Spinach
• Mustard greens
• Water cress

Moderately Fast Growing Vegetables - Plants that yield leaves and shoots or a fully mature within 26-45 days.

• Romaine Lettuce
• Baby Carrots
• Parsnip
• Lettuce (leaf)
• Radish – Winter
• Turnip

Reasonably Fast Growing Vegetables - Plants that yield leaves and shoots or a fully mature within 46-50 days.

• Beet
• Broccoli
• Okra
• Snap Bean (Green Bean)
• Summer squash – Scallop
• Summer squash – Zucchini
• Cauliflower
• Cucumber Slicing
• Kohlrabi
• Peas - Snow (Sugar)
• Peas – Snap
• Peas – Garden (Shell)

Fastest Growing Vegetables

► Green Onions 

Green onions of various types produce tops very quickly which can be harvested develop well before the bulb is mature. The types available are:

• Green Onions - regular onions, for which the tops can be partially harvested before they form a bulb
• Spring Onions - these have small bulbs that mature quickly
• Scallions - these varieties never form a bulb

You can sow seeds indoors 5 -6 weeks before the last frost in your area and wait a couple of weeks direct sow in the garden after the last frost. 

► Radishes - Fast and Easy to Grow

Radishes should be grown as quickly as possible and eaten early as they can become hard or pithy when older. With proper care radishes can be harvested within 20-30 days. Some varieties grow faster than others.

► Salad Greens - Rapid Harvest

Various lettuce types can be harvested quickly by picking some of the leaves. Super quick maturing types such as arugula can be harvested as baby greens within 3 weeks. Most salad greens can be harvested within 21-55 days. Rocket and spinach also grow quickly when harvested as 'baby' types.

► Turnips and Beets - Two Crops in One

For these plants the tops can be trimmed as the plants grow well before the bulbs are mature. If the plants are kept growing quickly, trimming some of the leaves will not affect the development of the bulbs. Time to the first harvest of the tops is 30 – 60 days.

► Leaf Lettuce

Varieties such as Romaine can be first harvested about 30 days after planting. Start to remove small leaves once they reach 3 inches in size (7 cm)

► Baby Carrots

Baby carrots can be harvested after about 30 days. Choose faster growing varieties and sow in bulk expecting to harvest them before they are fully mature. Standard carrot varieties take 50 - 80 days to mature.

► Spinach

Spinach matures after 4-6 weeks, but can be harvested as 'baby' leaves

► Kale, Mustard Greens and Watercress 

Many varieties can be harvested early and many are fast growers. Baby leaves can be picked starting from about 25 days. Most take about 50 to 65 days to mature, but can be continually harvested in the mean time.

► Green Peas

The various varieties yield pods that can be harvested as the plant grows. Snow and Sugar peas and other types are intended to be eaten before the peas develop in the pods. These develop sooner that the traditional varieties. Peas can be tall, semi-dwarf and dwarf varieties. Snow peas take only about 10 days to germinate and are ready for harvest in about 45-60 days.

► Bush Beans

Most varieties of bush beans can be harvested within 40-65 days from planting, but can be picked as 'baby beans'.

► Cucumbers

Most varieties can be harvested after 50-70, but some of them can be picked when small.

► Squash

Many varieties of squash, including zucchini, can be harvested after about 50-70 days. Small squash have a sweet taste and have very versatile uses.

Growth Rates of Common Vegetables with Fastest Listed First

Vegetable	Early Picking	Days to First harvest	Days to Maturity	Comment
Spring Onion	early, leaves	21	21-30
Arugula and other Salad Greens	early, leaves	23	23-55
Green Onion – Scallions	early, tops	24	24-140
Radish - Spring		25	25-40	Radishes larger than 2 in diameter are often pithy and unusable.
Spinach	early, leaves	25	45-60	Harvest the entire crop when plants begin to show signs of bolting.
Mustard Greens	early, leaves	25	50-65
Water Cress	early, leaves	25	50-65
Romaine Lettuce	early, leaves	30	30-90
Baby Carrots	early	30	30-60
Parsnip	early, tops	40	110-130	Can be overwintered in the ground, mulch and dig before new growth starts in spring.
Lettuce (leaf)	early, leaves	45	45-60	Harvest outer leaves, hot weather causes bitterness.
Radish – Winter		45	45-70	Can be left in the ground until frost.
Turnip	early, tops	45	45-70	Foliage can be harvested for greens.
Beet	early, tops	50	50-70	Up to 1/3 of the beet foliage can be harvested for greens without harming the root.
Broccoli		50	50-65	Harvest before yellow flower buds start to open, side shoots can be harvested after main head is removed.
Okra	early, leaves	50	50-65	Harvest frequently to maintain productivity.
Snap Bean (Green Bean)		50	50-70	Harvest when pods are pencil size in thickness.
Summer squash – Scallop		50	50-60	Harvest when skin is soft.
Summer squash – Zucchini		50	50-60	Harvest every 2 to 3 days when fruit are 2 in diameter.
Cauliflower		55	55-80	Blanch heads when 2-3 across by carefully tying leaves over heads.
Cucumber Slicing		55	55-65	1 to 2 diameter, harvest plants every 2 to 3 days.
Kohlrabi	early, tops	55	55-70	Store with leaves and roots removed.
Peas - Snow (Sugar)		55	55-85	Harvest when pods are long and thin, just as the seeds begin to develop.
Peas – Snap		55	55-85	Pick when seeds are nearly full size.
Peas – Garden (Shell)		55	55-85	Harvest when peas are full size.
Cabbage		60	60-90	Harvest when heads are large and solid.
Carrot		60	60-80	Harvest when orange shoulder pushes through the soil.
Pepper - Hot		60	60-90	Use gloves when harvesting.
Pepper – Sweet		70	70-90	Usually harvested when green, but can be left on plant until red, orange, yellow or purple.
Sweet Corn		70	70-105	Mature kernels exude milky sap when punctured.
Tomato		70	70-90	Harvest fully ripe for best flavor.
Eggplant		75	75-90	Fruit should have shiny finish.
Muskmelon Cantaloupe		75	75-100	When mature, stem separates easily from melon.
Watermelon		80	80-100	Harvest when 'belly' turns from white to creamy yellow.
Pumpkin		85	85-120	Harvest when uniformly orange, leave 3-4 of stem.
Winter Squash		85	85-120	Rind should be hard and difficult to puncture with fingernail.
Garlic		90	90	Harvest when foliage topples over and dries or just before first frost.
Onion		90	90-120	Harvest when tops fall over and begin to dry.
Potato		90	90-120	Dig when tops turn brown and die.
Sweet Potato		100	100-125	Harvest just before or after a vine killing frost.