While I study plant biotechnology, I often think about how bad it is for nature when people don’t know enough about it or spread false information. That is why I am so passionate about bringing people and nature closer together again. Favourite fruit: raspberries, strawberries and pineapple Favourite vegetables: courgettes, broccoli and cucumbers.
Rhododendron blooms are a favourite among many gardeners. However, to ensure lush flowering it must be properly cared for and protected from disease. Find out all about rhododendron care.
Rhododendrons (Rhododendron) are one of the largest genera within the heath family (Ericaceae). With more than 1,000 species worldwide, the rhododendron is geographically represented almost everywhere. Therefore, it is not surprising that it can be affected by a variety of pests and diseases. We give you advice on how to take good care of your rhododendron and keep pests and diseases away so it can keep blooming beautifully.
Rhododendrons are relatively easy to care for. However, they do require some attention from you at certain times of the year. We reveal what you should pay attention to when caring for them. Before we start, though, there are a few things you should think about before you even plant a rhododendron. Rhododendrons prefer a slightly acidic soil and detest waterlogging. However, many soils, especially in southern Germany, tend to be neutral to slightly alkaline. So, it might be best to make a big hole for planting and fill it with special rhododendron soil.
Rhododendron plants require regular watering, particularly when they are still small. But waterlogging should not happen because the rhododendron is a shrub with shallow roots and is very sensitive to it. There is less need to water a rhododendron as it gets bigger and older because the roots are stronger. Signs of the need for watering may be drooping buds during flowering, or else curling leaves.
Note: water your precious plant at slightly longer intervals but with a little more water. During dry spells in particular, too small amounts of water can evaporate quickly before penetrating the soil.
Rhododendrons are especially happy with long-term fertilisation. The best time for this is in the spring, which means shortly after planting for freshly planted shrubs. Work the fertilizer into the root zone from the top down so that the nutrients can be better absorbed by the soil. To help the plants grow, mix bone meal, compost, and/or coffee grounds with the soil you dug up and then put it back in the hole you dug. All of these fertilizers are completely natural, make the soil a little more acidic, and help the plants and animals that live there. While coffee grounds lower the pH of the soil, they are not a great source of nutrients. Compost, on the other hand, provides nutrients over a long period of time. Bone meal does not affect soil pH but also provides long-term nutrient release with a high nitrogen content. If you’d rather not use slow-release fertilizers and instead fertilize your plants regularly, stop fertilizing in early October to make the plants go into dormancy.
Giving your favorite shrubs that are already well established in the garden a mix of mineral and organic fertilizer a few weeks before they flower is what experts say you should do. Learn more in this video.
You can also buy rhododendron fertilizers that are made just for this plant. These fertilizers have all the nutrients it needs and also add back some fully organic nutrients over time. A plant-based fertiliser such as our Plantura Hydrangea Food is also suitable for rhododendrons. The rhododendron gets its nutrients from the slow-release fertilizer over a longer period of time. It also gives the plant iron.
Note: Under special circumstances, a second fertilisation may also be carried out in the summer. This is only needed if the plant’s leaves turn yellow and die because it doesn’t have enough nutrients.
In principle, rhododendrons do not need special pruning to bloom profusely. But over time, the shoots will become more lignified, so it makes perfect sense to do rejuvenation pruning as needed. You should do radical rejuvenation pruning on your rhododendron before it flowers so that you don’t waste its energy and so that nesting birds aren’t disturbed.
Cut off any old shoots with sharp rose shears so that the bush’s bare interior can get light again. It is important to make sure that you cut the shoots at an angle. If this happens, dew or rainwater won’t be able to gather on the shoots’ open parts, which could let diseases in. You can do a full maintenance pruning right after flowering if you don’t want to do a radical rejuvenation pruning but still want to keep the shape of your rhododendron. This means cutting off any shoots that are unsightly, sick, or hurt until you are happy with the way your favorite plant grows again.
With their beautiful blooms and attractive foliage, rhododendrons make a wonderful addition to gardens. But proper watering is crucial to keeping these flowering shrubs healthy and vibrant. Learning the ideal frequency for watering rhododendrons will help you provide the right care.
Rhododendron Water Needs
Rhododendrons have relatively shallow, fibrous root systems compared to other shrubs and trees. This means they prefer consistently moist (but not soggy) soil. Drying out too much causes stress for rhododendrons. During the active growing season, rhododendrons require about 1-1.5 inches of water per week from rain or supplemental irrigation.
Watering Newly Planted Rhododendrons
For rhododendrons that were recently planted, more frequent watering is important to help establish new transplants. Aim to water new rhododendrons about twice per week during the first year. Provide about 15-20 gallons of water per session This helps encourage deeper root growth Once established, rhododendrons can get by with less frequent irrigation.
Watering Established Rhododendrons
For rhododendrons that have been in the ground for over a year, you can water less often. Established rhododendrons generally only need supplemental water during periods of drought, which is around 2-3 weeks without rainfall. Apply about 15-20 gallons of water per plant during each watering session.
Check the soil moisture before watering. Stick your finger into the soil around the plant. If the top few inches of soil are dry, it’s time to water. You can also assess if plants are drought stressed by looking for drooping or curling leaves.
Best Practices for Watering Rhododendrons
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Water in the early morning or evening to reduce evaporation loss, Avoid watering during the heat of midday
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Use drip irrigation or soaker hoses to target the soil. Avoid sprinklers that wet foliage, which can encourage fungal disease.
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Maintain 2-3 inches of organic mulch around rhododendrons to help retain soil moisture. Replenish as needed.
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Improve drainage in clay soils to prevent puddling. Rhododendrons dislike soggy soils.
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Group rhododendrons together to create a shaded microclimate that helps conserve moisture.
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Add compost or other organic matter to improve moisture retention in sandy soils.
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During periods of drought, prioritize watering plants that are still establishing over mature, established shrubs.
Signs Rhododendrons Need More Water
Watch for these indicators that your rhododendrons would benefit from more frequent watering:
- Leaves curling or drooping
- Flower buds drying up and falling off
- Leaves browning at the edges or tips
- Lackluster leaf growth and few new shoots
- Branches dieback
Signs of Overwatering Rhododendrons
Too much water can be just as detrimental for rhododendrons. Monitor for these problems:
- Mushy, discolored roots
- Yellowing lower leaves
- Smaller than normal leaves
- Stunted growth
- Leaves dropping excessively
Adjusting Water for Rhododendron Varieties
There are over 1000 species and cultivars of rhododendrons to choose from. Some types have slightly different water requirements:
- Native rhododendrons are adapted to regional rainfall patterns.
- Heat-tolerant varieties can handle more sun exposure with adequate irrigation.
- Dwarf rhododendrons generally require more frequent watering than full sized varieties.
Getting to know the characteristics of your particular rhododendron will allow you to tailor watering appropriately.
Proper watering is key to maintaining healthy rhododendrons. New transplants need more frequent irrigation to establish, while mature plants only require supplemental water during drought. Checking soil moisture, mulching, and monitoring plant signs are good ways to determine when your rhododendrons need to be watered. With the right watering regimen, your rhododendrons will thrive for years to come.
After flowering: deadheading rhododendron flowers
After you have done a comprehensive pruning, you can still continue to do something good for your rhododendron. To do this, simply deadhead all the withered flowers on the remaining shoots. This promotes bud formation the next year and eliminates spore foci, which prevents infestation by fungal pathogens.
The rhododendron genus is especially prone to fungal diseases, but animal pathogens can also do a lot of damage to its evergreen leaves.
You want to know who’s behind Plantura?
While I study plant biotechnology, I often think about how bad it is for nature when people don’t know enough about it or spread false information. That is why I am so passionate about bringing people and nature closer together again. Favourite fruit: raspberries, strawberries and pineapple Favourite vegetables: courgettes, broccoli and cucumbers.
Rhododendron blooms are a favourite among many gardeners. However, to ensure lush flowering it must be properly cared for and protected from disease. Find out all about rhododendron care.
Rhododendrons (Rhododendron) are one of the largest genera within the heath family (Ericaceae). With more than 1,000 species worldwide, the rhododendron is geographically represented almost everywhere. Therefore, it is not surprising that it can be affected by a variety of pests and diseases. We give you advice on how to take good care of your rhododendron and keep pests and diseases away so it can keep blooming beautifully.
Rhododendrons are relatively easy to care for. However, they do require some attention from you at certain times of the year. We reveal what you should pay attention to when caring for them. Before we start, though, there are a few things you should think about before you even plant a rhododendron. Rhododendrons prefer a slightly acidic soil and detest waterlogging. However, many soils, especially in southern Germany, tend to be neutral to slightly alkaline. So, it might be best to make a big hole for planting and fill it with special rhododendron soil.
Rhododendron plants require regular watering, particularly when they are still small. But waterlogging should not happen because the rhododendron is a shrub with shallow roots and is very sensitive to it. There is less need to water a rhododendron as it gets bigger and older because the roots are stronger. Signs of the need for watering may be drooping buds during flowering, or else curling leaves.
Note: water your precious plant at slightly longer intervals but with a little more water. During dry spells in particular, too small amounts of water can evaporate quickly before penetrating the soil.
Rhododendrons are especially happy with long-term fertilisation. The best time for this is in the spring, which means shortly after planting for freshly planted shrubs. Work the fertilizer into the root zone from the top down so that the nutrients can be better absorbed by the soil. To help the plants grow, mix bone meal, compost, and/or coffee grounds with the soil you dug up and then put it back in the hole you dug. All of these fertilizers are completely natural, make the soil a little more acidic, and help the plants and animals that live there. While coffee grounds lower the pH of the soil, they are not a great source of nutrients. Compost, on the other hand, provides nutrients over a long period of time. Bone meal does not affect soil pH but also provides long-term nutrient release with a high nitrogen content. If you’d rather not use slow-release fertilizers and instead fertilize your plants regularly, stop fertilizing in early October to make the plants go into dormancy.
Giving your favorite shrubs that are already well established in the garden a mix of mineral and organic fertilizer a few weeks before they flower is what experts say you should do. Learn more in this video.
You can also buy rhododendron fertilizers that are made just for this plant. These fertilizers have all the nutrients it needs and also add back some fully organic nutrients over time. A plant-based fertiliser such as our Plantura Hydrangea Food is also suitable for rhododendrons. The rhododendron gets its nutrients from the slow-release fertilizer over a longer period of time. It also gives the plant iron.
Note: Under special circumstances, a second fertilisation may also be carried out in the summer. This is only needed if the plant’s leaves turn yellow and die because it doesn’t have enough nutrients.
- For lovely hydrangeas in pots with lots of blooms
- Prevents common deficiency symptoms & supports healthy plant growth
- Child-safe fertilizer that lasts a long time and doesn’t contain any animal products
You can find out more about how to properly fertilise your rhododendrons here.
In principle, rhododendrons do not need special pruning to bloom profusely. But over time, the shoots will become more lignified, so it makes perfect sense to do rejuvenation pruning as needed. You should do radical rejuvenation pruning on your rhododendron before it flowers so that you don’t waste its energy and so that nesting birds aren’t disturbed.
Cut off any old shoots with sharp rose shears so that the bush’s bare interior can get light again. It is important to make sure that you cut the shoots at an angle. If this happens, dew or rainwater won’t be able to gather on the shoots’ open parts, which could let diseases in. You can do a full maintenance pruning right after flowering if you don’t want to do a radical rejuvenation pruning but still want to keep the shape of your rhododendron. This means cutting off any shoots that are unsightly, sick, or hurt until you are happy with the way your favorite plant grows again.
We have put together more tips and tricks for pruning your rhododendron here.
How Often to Water Rhododendron: Your Ultimate Guide
FAQ
Can rhododendrons be overwatered?
How often should I water rhododendrons?
How do you know if a rhododendron has too much water?
Do rhododendrons like full sun or shade?
How often should rhododendrons be watered?
To ensure your rhododendrons receive their fair share, water them twice a week. Mulching remains your best friend in this situation too. If there’s a dry spell or a full-blown drought, you should increase the frequency of watering. Just remember to keep the soil moist but not waterlogged. Too much water is never a good thing!
Should rhododendrons be watered in the morning?
Water your rhododendrons early in the morning. Watering your rhododendrons in the morning will allow the water to soak into the soil before the hottest part of the day. Rhododendrons will be able to absorb the water more quickly and efficiently. Check the soil before watering. Before you water your rhododendrons, make sure to check the soil.
How do I know if my Rhododendron needs watering?
The best way to gauge rhododendron watering needs is to check the moisture level of the soil by inserting your finger about an inch deep. If the soil feels dry, it’s time to water. However, if the soil feels moist, hold off on watering until it dries out a bit. Take into account the rainfall in your area during the fall.
Should rhododendrons be watered in a dry climate?
When it comes to watering rhododendrons in a dry climate, there are some special considerations to keep in mind. Rhododendrons are an evergreen shrub that thrive in moist, acidic soils, and they need a significant amount of water in order to survive and flourish.
How do you care for a rhododendron?
Mulch around the plant. Mulching helps to retain moisture in the soil, which can help to reduce the need for watering. Avoid overwatering. It is important to avoid overwatering your rhododendron, as this can lead to root rot. Water only when the soil is dry to the touch.
Do rhododendrons need supplemental watering?
If there are extended periods of dryness or if your rhododendrons are exposed to drying winds, occasional supplemental watering may be necessary. However, ensure that the soil has good drainage to prevent waterlogging.