As a general rule of thumb, you should water an established vegetable garden 1 to 3 times per week. Most veggies need 1 to 2 inches of water per week, so spread that out across your weekly watering sessions as you see fit. However, you need to know a lot more than the general rule to figure out how often to water your vegetable garden.
For one, the amount of water and frequency of watering your plants need varies with the age of the plant. Newly planted seeds should be watered every day. Different types of plants and different soil types also have different watering needs. Our garden watering tips will walk you through exactly how to tell how often to water your vegetable garden with all its specific quirks and potential problems.
- 1. Learn to water your garden by its soil type
- 2. Vegetable plants have different water needs
- 3. Change the irrigation schedule with plant life cycle stages
- 4. Root depth is an essential factor
- 5. Water more often during heat waves
- 6. Irrigate less often in a humid climate
- 7. Adjust watering during windy periods
- 8. Factor in rainfall
- 9. Water less often if you use mulch
- 10. Adjust the irrigation schedule to your garden type
- 11. Water early in the morning
- 12. Spread water on the soil, not the leaves
- 13. Measure how much water you provide
- 14. Check soil moisture level
- 15. Watch for signs of underwatering and deal with drought stress
- 16. Keep an eye on overwatering symptoms and learn to fix waterlogged soil
- FAQ
1. Learn to water your garden by its soil type
The mineral part of the soil is made of sand, silt, and clay particles. Depending on which type of mineral particles prevails, your garden has one of these soil types:
- Clayey soil
- Sandy soil
- Silty soil
- Loam (a balanced mix of the three)
Each type has a different behavior towards water, and so they have different irrigation needs.
How often to water sandy soil
Water sandy soil 2 to 3 times per week and increase frequency during high heat and drought. Sandy soil has large, coarse particles that make it gritty to the touch. Its large pores and loose texture absorb and release water quickly into the lower layers of the soil. Just a tiny amount stays in the topsoil and is available for root systems.
Water-holding capacity: Low
Drainage: Excellent
Fertility: Low in organic matter. Requires soil amendments (compost, humus, manure) periodically.
Better for: Tap-root plants like carrots, turnips, parsnips, beets, and celery.
How to water sandy soil: More frequently and for shorter periods. For example, apply 1 inch of water in two sessions of 0.5 inch per application rather than in one session. The recommended flow rate for sandy soils is 0.4 to 0.8 inches per hour.
How often to water clay soil
Water clay soil deeply, slowly, and less often. One watering session per week typically suffices. Increase frequency during high heat and drought only if plants show signs of underwatering.
Clay soil has fine particles and tiny pores that slow water absorption and release. It feels smooth, like talc, and holds water and nutrients well.
Water-holding capacity: High
Drainage: Poor. Amend with organic matter (compost, manure, mulch, leaf mold) to loosen the structure and improve drainage.
Fertility: High in nutrients.
Best for: Shallow-rooted plants like spinach, lettuce, cabbage, and broccoli.
How to water clay soil: Apply water slowly, in longer sessions, to fit its absorption speed. This way, you prevent runoff and puddling. Cornell University recommends a flow rate of up to 0.2 inches per hour for soils high in clay (silty clay loams and clay soils).
How often to water loamy soil
Irrigate loamy soil once a week. Increase frequency during drought and high heat and stop watering when it rains. Loam has a balanced mix of silt, sand, and clay particles, giving it good water-holding capacity with adequate drainage.
Water-holding capacity: Good
Drainage: Good
Fertility: High in nutrients with a good texture. Apply compost yearly to maintain it.
Best for: You can grow a variety of vegetables on loam soil.
How to water with loamy soil: Irrigate deeply and less often. Once a week is typically enough, except in periods of high heat or windy areas. Use a 0.4 to 0.8 inches per hour flow rate and apply about 1 inch of water per week if there is no rain.
Test your soil
The surest way to learn the soil type in your garden is to take a sample and have the soil tested at your local Extension Office.
You can also use a jar and do a DIY soil test. Here’s how:
- Collect soil from your garden to fill about ⅓ of a jar.
- Sift through a sieve and remove all pieces of wood, roots, and other debris.
- Put it into the jar.
- Add water to fill the jar, but leave some space at the top.
- Close the jar and shake it to mix the water with the soil, then put it on a level surface and let it settle.
The sand particles are the heaviest and largest. They need about a minute to settle down and form a compact layer. Mark its top level and measure it.
The silt layer takes about 2 hours to define. Mark it and measure it.
Clay particles are fine and light. They need about 48 hours to clear the water and settle on top of the silt layer.
You have sandy soil if the jar’s sand layer is the thickest. If clay particles are dominant, it’s clay soil. With about equal layers, you’ve got loam.
2. Vegetable plants have different water needs
Water needs differ from plant to plant. Herbs like sage, rosemary, and thyme need less water and can die if overwatered. Leafy greens are also less demanding, while fruiting vegetables, like tomatoes, cucumbers, zucchini, and squash, need more water to grow successfully.
Here’s a table with the average water needs for the most common vegetables and plants grown in home gardens.
Plant type | Water requirements per square foot per week |
Arugula | 1 to 1.5 inches |
Basil | 1 to 1.5 inches |
Beans | 1 to 2 inches |
Bell peppers | 1 to 2 inches |
Broccoli | 1 to 2 inches |
Brussels sprouts | 1 to 2 inches |
Cabbage | 1 to 1.5 inches |
Chives | 1 to 1.5 inches |
Carrots | 1 inch |
Cauliflower | 1 to 2 inches |
Cucumbers | 1 to 2 inches |
Dill | 1 to 1.5 inches |
Eggplants | 1 to 2 inches |
Kale | 1 to 1.5 inches |
Lettuce | 1 inch |
Peas | 1 inch |
Pumpkins | 1 to 2 inches |
Radishes | 1 inch |
Spinach | 1 to 1.5 inches |
Tomatoes | 1 to 2 inches |
The water amount and irrigation frequency varies across their growing process. Let’s see how you can adapt the watering schedule for the best results throughout your plants’ life cycles.
3. Change the irrigation schedule with plant life cycle stages
Your vegetable garden needs different amounts of water as plants pass through their life cycles. Across the growing season, from seed to harvest, you’ll need to adjust:
- Water amount
- Irrigation frequency
- How you apply the water
Here are a few watering tips to help you start a vegetable garden on the right foot and continue watering it correctly as it grows.
Seed stage: Apply a soft mist of water a few times daily
Water seeds twice daily (or more) to keep the topsoil moist and support germination. Apply a small amount of water in a soft mist using sprinklers, a garden hose, or a watering can with a nozzle. Avoid strong jets of water. They might displace the seeds and expose them to dry air.
Seedlings and transplants: Irrigate 3 to 5 times a week
Young plants need water within reach since they can’t access deep underground reserves. Irrigate daily or every other day while their roots develop.
Drip irrigation and soaker hoses are the best devices for watering young plants. Their stems are fragile, and strong jets of falling water can easily break them. Apply a soft mist if an overhead watering system is your only choice.
Established plants: Water 1 to 3 times a week
By now, your plants have large enough roots to start exploring the soil depths for water. Reduce watering frequency gradually until you only irrigate 1 to 3 times weekly. Adjust frequency depending on soil type and rain conditions.
It’s also time to train your veggies for drought tolerance. Water deeply and less often. Schedule a new watering session when vegetable plants show signs of stress.
Avoid overhead sprinklers since they expose plants to fungal diseases. Use a drip irrigation system, install soaker hoses, or use a garden hose with a wand. Do your best to apply the water at the base of the plant and avoid sprinkling the leaves.
Flowering and fruiting: Increase watering amount and frequency
Increase the water you offer weekly when your tomatoes and cucumbers form fruit. Also, try to keep the moisture level constant. Adding a lot of water after a drought spell can cause the fruits’ skin to break. Decrease the water amount when fruits ripen to get a more intense taste.
4. Root depth is an essential factor
Vegetable root depth has a crucial influence on how well plants can access water in the soil. Shallow roots only use the water available in the soil’s top layers. Deep-rooted veggies can dip into reserves hidden deep in the ground. Let’s see how your watering strategy should adapt to maximize this tip.
Water shallow-rooted vegetables most often
Shallow-rooted vegetables and herbs dig their roots only 12 to 18 inches deep into the ground. They have low drought tolerance and need more frequent watering during the summer. Sandy soil increases their vulnerability.
Some examples of veggies with shallow roots are:
- Celery
- Chives
- Fennel
- Endive
- Lettuce
- Onions
- Radishes
- Shallots
- Spinach
- Swiss chard
This is the main category you can expect to water daily during a hot spell. Shallow-rooted veggies are also the first to require irrigation after rain.
Keep an eye on moderate-rooted vegetables for signs of stress
Moderate-rooted plants go as far as 18 to 24 inches into the ground. They are less sensitive to drought than shallow-rooted species but still need more water during high heat. Depending on the soil quality, you might need to double the watering frequency during a prolonged drought. Among the most popular vegetables and herbs from this group are:
- Beets
- Cabbage
- Broccoli
- Cauliflower
- Cucumbers
- Kale
- Okra
- Peppers
- Potatoes
- Turnips
Don’t water deep-rooted vegetables too often
Deep-rooted species dig their roots deeper than 24 inches into the ground. They use moisture reserves in the lower soil layers, safe from heat and evaporation. If trained well when developing their roots, they only need a slight increase in watering during drought.
Some of the deep-rooted veggies in your garden are:
- Asparagus
- Sweet corn
- Lima beans
- Melons
- Parsnips
- Pumpkins
- Squash
- Tomatoes
5. Water more often during heat waves
High temperatures increase evaporation. A smaller amount of the water you supply through irrigation soaks into the ground to feed the plant roots. Most is absorbed by the dry, hot air from the soil surface.
To avoid the heat and reduce water loss, always irrigate as early in the morning as possible during heat waves. Also, water your garden more often to help vegetables deal better with the heat.
6. Irrigate less often in a humid climate
Humid air has less space to absorb extra water, and evaporation is incredibly slow. If you live in Mississippi or Louisiana, you know what we mean. Despite being oven-hot, sweat lingers on your skin, and you can’t cool off. It’s the same with the soil.
With all that hot air, moisture remains in the ground for a long time. High air humidity prevents evaporation. You risk fungal diseases in such weather if you add too much water to your veggie garden. Water less often and check the soil moisture before you irrigate.
7. Adjust watering during windy periods
Wind dries out your plants and soil faster. It can also mislead your perception during a drought period. You might underestimate how fast water evaporates from the soil since you’ll feel pleasant air currents and less heat. Make a habit of checking the soil moisture in your garden during windy summer weeks and adjust the watering frequency as necessary.
8. Factor in rainfall
Heavy rainfall of 1 to 2 inches per square foot is a good reason to postpone watering your garden until next week. But, sometimes, despite the loud noise and a curtain of water falling from the sky, only a tiny amount of water reaches the soil. If you stop watering, your veggies might suffer.
How do you know how much it rains and when it’s enough? Experienced gardeners use a rain gauge. It’s a simple, inexpensive, easy-to-use device that measures rainfall amounts per square foot.
9. Water less often if you use mulch
Applying 2 to 3 inches of mulch on your garden beds is an excellent way to save water. Mulch keeps the soil cooler and reduces evaporation by up to 50%.
Water remains longer in the ground, and more of what you apply is accessible to plants. This also means that with mulch on your soil, you must reduce the water used during a week to avoid root rot.
10. Adjust the irrigation schedule to your garden type
In-ground garden beds, raised beds, and gardening containers hold water differently, even with the same soil type. Adjust your watering schedule depending on how you’re growing your veggies.
Pro tip: For advice on how to grow veggies and which veggies to grow, check out these vegetable garden ideas!
In-ground beds
Vegetables and herbs planted directly into the soil in in-ground beds benefit from the best thermal insulation. In-ground beds warm up slower during the summer, so moisture is better contained. A kitchen garden with in-ground beds can be watered 1 to 3 times weekly depending on weather conditions, soil type, and plants.
Raised beds
The raised part of a garden bed is more exposed to heat and dry air. Raised garden beds warm up faster and earlier during summer and lose moisture quickly. Plants grown in raised beds must be watered more often during high temperatures and dry spells. Apply water 2 to 3 times a week, up to once every other day, depending on the temperature.
Container gardening
The smaller the soil mass, the faster the moisture loss. Container gardens are first to dry out, especially if kept in direct sunlight. Small ones might need watering twice a day during a hot spell with temperatures over 90°F.
11. Water early in the morning
The best time of day to water your garden is early morning. Temperatures are low, the soil surface is not yet exposed to the hot mid-day sun, and evaporation is minimal.
Irrigate your vegetables before 9 – 10 a.m. in spring and fall. During summer, wake up earlier and water the garden by 6 – 7 a.m. to avoid the heat of the day as much as possible.
If early irrigation is not an option, the second best time to do it is late afternoon to early evening. However, prolonged leaf wetness overnight promotes fungal diseases. Avoid sprinkling water on the plant leaves when watering in the evening since the sun is no longer there to dry them.
12. Spread water on the soil, not the leaves
The best garden irrigation methods deliver water to the soil surface, allowing it to soak quickly into the root zone. Drip irrigation and soaker hoses are the most effective of them. They apply water slowly, allowing easy absorption even on clay soils. You can also install a timer for automatic control.
A garden hose with a watering wand is another good but more time-consuming option. Watering cans are also suitable for small garden beds or containers.
13. Measure how much water you provide
Applying 1 inch of water per square foot translates into about 0.63 gallons. For a 4×8 feet garden bed, that means 20 gallons of water, and for a 10×10 feet planted area it means 63 gallons.
To know when you’ve applied the right amount of water and it’s time to stop the irrigation system, you need to measure the water you put into the soil.
The easiest way to do it is by using a hose-end water flow meter. You install it at the outdoor faucet. It tells you how much water you used since you opened the faucet to irrigate. Hose meters are readily available online and from local garden shops.
14. Check soil moisture level
With so many factors influencing how water behaves in the soil, the best way to avoid underwatering and overwatering is to test the moisture level occasionally. You can do this using a soil moisture meter or the trowel test.
The soil moisture meter has a rod you stick into the soil a few inches deep and a mechanical scale or a digital screen showing the moisture level. It’s an accessible device that is so easy to use that you can even try it when gardening with your children.
You’ll need to work a bit more on the trowel test. This one involves digging. Dig a hole into a free area of your garden bed with a trowel a couple of inches deep. Take some dirt in your hand and squeeze. If it feels moist, you don’t have to water just yet.
15. Watch for signs of underwatering and deal with drought stress
Suspect underwatering when:
- Vegetable plants begin to wilt.
- Plant leaves start yellowing from the base of the plant or get brown spots. They have a dry, crispy texture and curl upwards.
- Fruits are small and dry.
- The soil is lightweight and dry.
Underwatering mostly happens during prolonged drought, when dry air and the absence of rain put a stretch on the soil moisture. Here’s what you can do to fight drought stress in your vegetable garden:
- Apply a layer of mulch 2 to 3 inches thick. It controls soil temperature and limits evaporation.
- Water deeply to replenish soil moisture.
- Provide shelter from sunlight (installing shade cloth is an excellent option).
- Use drip irrigation to reduce evaporation.
- Water more during the plants’ peak times, when needed most. For example, carrots when they develop their roots, tomatoes when in flower and growing fruit.
- Irrigate as early in the morning as you can.
16. Keep an eye on overwatering symptoms and learn to fix waterlogged soil
Most overwatering signs are similar to drought stress, but some differences can tell you which one is damaging your veggies if you notice them carefully:
- Old and new leaves are yellowing and some get brown spots.
- Leaves have a soft, limp texture and curl downwards.
- Blisters show up on leaves.
- Fruits’ skins begin to crack.
- The entire plant slows down growth.
Waterlogged soil is a real menace to plant health. Here are a few strategies to correct the soil structure and improve overall drainage:
- Take off the mulch layer (if any) and plant cover crops to use some excess water.
- Add organic matter to improve texture in clay soil.
- Plant on raised garden beds or convert to container gardening.
- Go no-dig. It’s a long-term method that improves the soil structure and drainage capacity.
- Level the yard to improve drainage.
- Install a drainage system like french drains to collect excess water.
- Collect rainwater to limit the amount reaching into the soil from the roof of your home.
FAQ about watering vegetables
The best time of day to water your vegetable garden is early morning. Evaporation is minimal, and the morning sun slowly dries out any water that gets on the leaves, protecting them from fungal diseases. Watering vegetable gardens in the afternoon is also an option, but you must apply the water at the soil level and avoid sprinkling the leaves.
Not all plants react the same way during drought, so adapt the watering accordingly. Increase irrigation frequency for vegetables that show signs of drought stress, like wilting that remains even when the day’s heat is gone. Keep the same watering frequency for deep-rooted plants like tomatoes and sweet corn if they don’t show signs of distress.
Veggies with shallow roots might need daily irrigation during drought and high heat. Radishes, lettuce, spinach, chives, and onions are some of the crops from this category.
Get the best watering system for your vegetable garden today
Keeping the vegetable garden properly irrigated is a delicate job that becomes much easier with the proper watering system. Put the watering can and the garden hose aside, contact a gardening specialist through Lawn Love’s convenient online platform, and consider a more effective watering strategy – such as drip irrigation – to get the most out of your garden.
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