How Often To Water Seedlings? The Best Schedule For Healthy Growth

Seedlings are young plants, and like all plants, they need water to survive. Water is required in the germination stage so seeds can sprout and send up shoots. As the plants begin to develop and put down roots, they need consistent moisture to grow big enough for flowering and fruiting. How often to water seedlings is a delicate balance: too little water will quickly kill seedlings, but too much water can cause them to rot, also leading to an untimely demise.

Starting seeds indoors allows for more control over the growing environment than direct sowing seeds into the garden, but either way, growers will have to learn how to water seedlings to help them grow strong.

You don't need much equipment when planting seeds, but you do need to provide them with enough moisture and understand how much light seedlings need. Get these details right and everything else will fall into place.

How Often to Water Seedlings at Different Stages

There are three basic growing stages for young plants: germination, seedling development, and the period of transplanting seedlings into the garden. Water requirements are different for each stage of seedling growth.

Stage 1 – Germination

Learning how to germinate seeds is the vital first step of plant growth, enabling the development of roots and shoots. Before germination, the seeds are dormant, and without water, they will remain so. Soaking seeds before planting will give them a head start. In the early stages, the goal is to keep the growing medium moist but not wet – or the seeds will rot.

Covering the seed pots with a clear plastic bag will keep in moisture. However, it is easier to use a lid designed to do the job, such as a humidity dome with vents, or a drip-irrigation lid that gently waters. You can find seed trays with humidity domes and drip-irrigation lids in the Gardening Know How Shop. Using a lid will mean you will rarely have to water during the germination process, but check every couple of days to see if the soil has started to dry out.

If seeds are uncovered, you will need to water them manually. Using a watering can is too disruptive for small seeds and delicate seedlings, so use a mister twice daily in the early stages.

Stage 2 – Seedling Development

After the seeds turn into seedlings, you’ll need to continue to water regularly. Plan to water them thoroughly whenever the soil feels dry, at least every few days. This is particularly important for the first few weeks since the roots need to grow and establish.

Bottom watering is usually best at this stage (more on this later), but you can water from above, using a small watering can. Direct the flow at the soil, rather than over the top of the seedlings.

Stage 3 – Hardening Off

Hardening off seedlings is the process of preparing the new plants for life in the garden. In addition to reducing the temperature and giving them gradually increasing amounts of outdoor time, start reducing watering. If you were watering every day indoors, cut that back to once every two days.

How often to water seedlings outdoors when they are transplanted depends on the weather, but you need to check the moisture level of the soil regularly, particularly during the weeks following transplant. They require adequate water to keep the seedlings strong and growing.

Best Watering Method for Seedlings

The best way to water seedlings is different for different stages of growth. During germination, misting the seeds works well, providing good coverage without excess moisture. Water seedlings with a spray bottle.

As the seedings develop, bottom watering is the best solution, and also works for seedlings in peat pots. Simply place the seed pots in a tray of water about an inch deep, allowing the water to wick up through the growing medium from below. This is better than direct watering since the seeds don’t get pushed down into the soil or washed out of place. Don’t remove the pots from the container of water until the surface of the growing medium is damp – it may take between 10 and 30 minutes.

The best time of day to water seedlings is usually the morning. This is certainly the case once you transfer the seedlings outside since you want the soil to dry out before the cool of the evening. But while they are indoors, it is okay to water seedlings whenever you notice the soil is dry.

How Much To Water Seedlings Each Session?

Whether watering seed trays or pots from above or below, you need just enough moisture that the soil feels moist throughout, but then the excess must be allowed to drain out. Once the seeds are transplanted outdoors, water sufficiently to keep the soil moist, at least for the first few weeks. Slowly reduce the amount of water.

Don’t apply too much water as it is easy to overwater seedlings. If the soil is wet instead of just moist, the roots can rot. Good drainage plays a critical role in this distinction.

Signs of Over and Underwatering

Seedlings will react if they aren’t getting enough water. Their leaves may wilt, look dry, and start to turn brown. However, the most common serious mistake gardeners make when watering seedlings is to give them too much. Overwatering is the primary cause of seedling death. If you are providing too much water, the seedlings may start to rot.

What Affects Watering Frequency?

Watering frequency varies depending on the type of soil, the type of container, and your climate. The ideal seed-starting mix should be well-draining with just enough moisture-retentive material. The container should have drainage holes.

More frequent watering may be required if high light levels or warm temperatures dry the soil faster. As the seedlings grow, you also may have to increase the amount of water.

In the garden bed, watering frequency depends on the climate. If it rains often, you’ll have less irrigation to worry about.

Should Watering Change as Seedlings Grow Larger?

Yes. Seedlings should be watered regularly to keep the soil moist. They should be watered when the surface of the soil is dry. Since bigger seedlings require additional water, they may uptake the available water more quickly.

Does the Type of Seedling Affect Watering Needs?

There is no general rule that vegetable seedlings need more water than flower seedlings or vice versa. The amount of water a seedling requires depends on the size of the seedling and the how dry the soil is.

Your Next Read

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