How To Water Hydrangeas For Beautiful Blooms

Beginners or those unsure about the watering process could use a moisture meter to measure soil moisture and ascertain when and how much to water your plants. This little gadget removes all the guesswork around knowing when and exactly how much to water your hydrangea plant.

This will prevent it from becoming water-soaked and dry, both of which lead to reduced growth or even plant death.

The moisture meter ranges from dry to wet or from 1 to 10. Once you stick the meter probe in the soil, you will get a reading after a minute. You then need to decide what to do based on the results, but to do that, you need to be familiar with your plant’s needs.  

Deep watering benefits most plants, including your hydrangeas, because it encourages them to root deep into the soil. Plants with roots closer to the surface are vulnerable. Meanwhile, deeply rooted ones survive better as they can withstand extreme weather fluctuations. 

If you are wondering how to water hydrangea deeply, saturate the soil about 8 inches deep or until the moisture reaches the plant roots. However, note there is a thin line between deep watering and over-watering. You should water slowly for an hour with a gentle stream and ensure no puddles in the saucer. 

Your technique for watering hydrangeas also depends on whether you planted them in the ground or pots. Potted plants will need regular and more water than ones grown in ground soil because their roots don't spread deep or wide.

Additionally, the foliage blocks rainwater from reaching the soil during the monsoon season. As a result, potted plants need more watering, especially in hot weather when water evaporates quickly. Hydrangeas planted in the ground may also need supplemental water during droughts.

On scorching days, water may evaporate before the hydrangeas can absorb it. You may need to water your plant more to ensure it is not dehydrated. However, increasing water to negate evaporation feels like water waste.

One way to conserve water and ensure your plant is hydrated is mulching. Mulch reduces evaporation and ensures the plant gets enough water. Add an inch or two of mulch around the base of your plant regardless of whether your plants suffer from dehydration because apart from retaining water, mulch also helps with weed suppression.

Most novice gardeners think watering the plants means letting the leaves and flowers take a drink. This is a mistake and does more harm than good. Water should be poured at the base of the plant, not the leaves or flowers, so aim the water source directly on the soil.

Doing so ensures that water ends up at the roots, where necessary. It also reduces the risk of fungal diseases.

It is better to replace the watering cans or hoses with soaker hoses or low-pressure tubing with attached emitters or pay attention while hand watering to ensure the water goes directly to the root system. 

Another reason to use a soaker hose is controlled water flow. When you water with a sprinkler or by hand, you likely use more water than necessary because the water comes out with unnecessary force and runoff. It will not give the roots enough time to absorb the water. 

A soaker hose has tiny perforations all along its length, which allow water to trickle out slowly. The low water pressure allows the water to flow directly to the plant's base. This means the water ends up in the root systems instead of evaporating from unnecessary places.

Different soil textures and structures respond to water differently, thus influencing the amount of water your plants need. For example, sandy soil has large particles, allowing water to drain quickly, which means it dries out faster. Meanwhile, clay soil has finer particles that hold moisture tightly.  

Hydrangeas need a lot of water but cannot tolerate too much water. They need just the right amount. This means if they are grown in sandy or heavy soil, they should be amended with compost and peat moss and watered accordingly. If not, their roots might decay, and their flowers may be small or not bloom at all.

Consider the hydrangea variety when determining water needs. Water needs for different hydrangea varieties vary due to differing growth habits, natural environments, and water usage.

Bigleaf varieties need more water because they have large, lush leaves that lose water quickly and thrive in moist, well-draining soil. Therefore, they are prone to wilting if the soil becomes dry.

You should plant panicle hydrangeas if you are looking for a more drought-tolerant species. They can withstand less frequent watering because their leaves are smaller and less prone to rapid water loss. Additionally, they are better at surviving in various conditions, including full sun.

Knowing how to keep hydrangeas hydrated can be tricky, particularly during the hottest months of the year. These plants are sensitive to drought and vulnerable during extreme heat. Thus, watering adequately is a must.

They use water to cool down during these months through evapotranspiration, so the hotter it gets, the more water hydrangeas need. During such weather, if the hydrangeas do not receive water for a week or more, they will dry out, and increasing the quantity of water will not help.

Age refers to the length of the plant’s life or life stage. Young and newly planted hydrangeas have shallow and fragile roots that require more water for root growth and strength. It is important to water plants less than a year old at least 3 times a week until established. Seedlings may need even more water, up to twice per day.

Watering mature plants is a little different. They do not need to be watered as frequently as young plants; instead, they need to be watered deeply so that water reaches the extensive roots deep in the ground. Water should preferably be supplied only when the first inch of soil has dried.

The water needs of Hydrangeas depend not only on their age but also on their volume or plant size: the bigger the plant, the larger will be the root, stem, leaf, and bloom parts. Therefore, a large plant requires more water to survive.

Large hydrangeas require more water to hydrate their extensive root system and compensate for the increased transpiration loss due to larger leaves. Deep watering is essential for these hydrangeas to reach the full depth of their roots.

You should water your hydrangeas according to the season. Spring and summer are when the plants need water the most. In spring, they come out of dormancy and need water to regain strength. In summer, they need extra water to beat the heat. They should be watered twice a week.  

Hydrangeas need different care during fall and winter, starting with reducing water. They do not need as much water during these seasons, especially in winter when they are dormant. Still, this does mean you can dry them out.

Rainwater quality is better for plants than water from any other source. Rainwater is pure hydration and is free of the salts, minerals, and treatment chemicals that build up in the soil over time, and these residues are detrimental to plants. The effects are worse in potted plants where accumulation is higher.

Rainwater is also a little acidic, around pH 7.  The ideal pH range for plants to grow is 5.5 to 6.5. Tap water and groundwater often have a pH range ranging from 8.5 to 10.5, which makes it very harmful for plants.

Most of us don't even think twice before watering plants with the faucet water. It is a quick, convenient way to get the job done. The thing is, while your hydrangeas have probably gotten by just fine with water from a tap until now, they might thrive better with water that's been left to rest.

That's because the water that flows straight from the faucet is cold - an average of 55 degrees Fahrenheit. This temperature can shock our indoor hydrangeas used to ambient room temperature.

For that reason, it's generally best to water your houseplants with room temperature water rather than cold water to prevent damaging the plant. Outdoor plants are less finicky, but if you're watering from a hose on a scorching day, ensure the water is not boiling.

Now that you know how to water hydrangeas, it is imperative to understand how often to water hydrangeas. On average, hydrangeas should be watered thrice a week, but as discussed above, it varies.

Consider watering even more frequently if you live in an area accustomed to drought and high temperatures to make sure the soil and roots underneath remain hydrated, even after the sunniest times of the day. 

If you plan to water by hand, it is difficult to measure how much water they are getting. In this case, it is best to get familiar with your soil. Stick your finger into the soil to get a good idea of how dry or wet it may be. It should be moist, not sopping wet.

Switch watering at twilight or in the afternoon to early morning. When your hydrangeas receive water in the morning, they retain the water needed to beat the day's heat peaks. Avoid irrigation in the evening since water pools within the soil, around the roots, and on the foliage, which encourages rot, fungal growth, and insects. 

If you water in the afternoon during hotter months, the water will evaporate instead of absorbing into soil and roots. The water droplets on leaves could also act as magnifying glasses, reflecting sunlight and potentially burning leaves. 

Underwatering is a common hydrangea watering mistake. It harms your plants in the long run, so look for signs indicating your plant is thirsty.  

• Brown, Crispy Flowers: Beautifully bloomed hydrangea suddenly dries out or falls off the plant when it needs water. Unfortunately, you cannot turn back time or rejuvenate those flowers. 
• Leaves Drooping: If the leaves are drooping, you can remedy this by giving your plant a hydrating soak. However, if this happens more frequently, consider changing its location and your watering regimen.
• Premature Leaf Dropping: Failure to remedy droopy leaves will lead to premature leaf shedding. Leaves fall off as part of their natural life cycle in autumn or winter, but it is always a bad sign if the leaves drop during summer.
• Yellow/Brown Leaves: The leaves are covered in dry splotches and their tips and edges turn yellow or brown. 
• Slow Growth: Hydrangeas will not bloom and grow to their expected size if they don’t get enough water. They will become dormant to survive. 
• Dehydrated Soil: The plant is underwatered if the above symptoms are accompanied by dry and dusty soil. Hydrangeas enjoy rich, moist, well-draining soil; it should feel damp. If the earth is dry as a bone, that's your soil's saying that you need to water it more often. 

After planting hydrangeas, gardeners can go overboard with watering because they are unsure how much water is too much. These plants enjoy moist soil but they can become waterlogged. Here are some common signs of an overwatered hydrangea that are preventing your hydrangeas from being as healthy as you would prefer.

• Yellow or Brown Leaves: Leaf discoloration can indicate underwatered and overwatered hydrangeas. When overwatered, the browning may be more toward the edges of the leaves.
• Wilted or Squishy leaves: The leaves will hang but not like those of an underwatered hydrangea. They look heavy and may feel soft and squishy. They are also discolored.
• Depressing Flowers: Flowers of overwatered hydrangea do not appear dry and wilted. They are deformed with only one or a few flowers in each head, leaving the plant looking sparse. The petals will feel soft and turn brown rapidly. Sometimes, there may not be any flowers at all. You can only learn from your mistake and correct it for the next blooming season. 
• Mold on the Soil: Mold on the soil surface is another indicator of overwatering in your hydrangea. Molds thrive in continuously wet environments, signifying that your plants are getting too much water or the soil is not draining well. They could be revived by transplanting before it is too late. 
• Water Pooling on Soil Surface: Problems associated with overwatering could manifest in water pooling on the surface after watering or heavy rainfall. Thus, soil adjustment or changing the watering schedule may be required. Hydrangea soil retains moisture, meaning water should not pool on the soil surface. Hold off on watering for a while to resolve this issue.
• Root Rot: Root rot is difficult to confirm since the root is decaying underground. However, if the symptoms mentioned above exist, root rot might exist. You can dig out the roots. If they are brown or black and soft, your suspicions are true. A healthy root is bright white and firm to the touch. Root rot will likely kill the shrub.