Location, soil, fertilizer, transplanting & more

Dear hydrangea friends,

Hydrangeas delight with their lush blooms – whether in the garden bed, in a pot, or on the balcony. To ensure your plants thrive, however, a few important points should be considered regarding location selection, care, soil quality, fertilization, and transplanting . We've compiled the most important information for you – based on our many years of experience in our nursery.

The right location for hydrangeas

Hydrangeas prefer a partially shaded to shady location , protected from direct midday sun and wind. A spot under light trees is ideal, where the plants receive morning or evening sun but are shaded during the day.

💡 Practical tip from the gardener: Bigleaf hydrangeas don't tolerate direct midday sun – this can cause the leaves to burn. Those with a sunnier location are better off choosing panicle hydrangeas (Hydrangea paniculata) – they are more resistant to heat and sun.

Most hydrangea species also require sufficient space to grow . Only when they have enough room will they develop evenly and form harmoniously grown shrubs.

The ideal planting time

The ideal time to plant or transplant hydrangeas is spring, before the plants fully sprout. Planting should take place by the end of July at the latest, so the hydrangea has enough time to establish before the first frost sets in.

Soil & pH: The basis for healthy hydrangeas

Hydrangeas thrive in slightly acidic, permeable, and nutrient-rich soil . Ideally, the pH is between 4.5 and 6.5 . Highly calcareous soils with a pH above 7.5 can lead to chlorosis (yellowing of the leaves) and should be adjusted.

Although hydrangeas prefer slightly acidic soils, alkaline soils are often tolerated – as long as the pH value is not permanently too high.

📌 Test pH value: Use pH test strips or digital soil testers to reliably determine the value.

👉 Here you can find suitable pH testing products for your garden.*

If the soil is unfavorable, a soil change can help: Dig a planting hole about four times the size of the root ball and fill it with acidic rhododendron or bog soil . This is available from garden centers and usually has the ideal pH for hydrangeas.

🌱 Tip: When planting, mix in some starter fertilizer like our Ullmann Hydrangea Fertilizer* . This promotes healthy growth.

After planting, you should water generously and keep the plant well moist for the first few weeks – especially during the growth phase.

Transplanting – when and how?

The best time to transplant is spring, before the hydrangea has fully opened its leaves. Fall planting is also possible, as long as there is enough time before the first frost (ideally plant by the end of July ).

If transplanting is only possible in summer, pay particular attention to its watering needs . Cover the plant with moist fleece for the first few days after transplanting to reduce evaporation through the foliage. Moist fleece not only protects the plant from sunburn but also helps retain moisture in the soil.

Watering & fertilizing – the be-all and end-all for healthy plants

Hydrangeas require a lot of water, especially in the hot summer months. Therefore, water regularly in the morning and evening , but avoid waterlogging —especially with potted hydrangeas. Ensure even soil moisture, but avoid wet feet.

Even in pots, hydrangeas should never dry out. Permeable soil with good drainage is also important.

Fertilize your plants with a specialized hydrangea fertilizer , ideally from spring until July at the latest, to promote good growth and maintain flower color.

👉 Click here for our proven hydrangea fertilizer*

Hydrangeas in pots – care, repotting & overwintering

Hydrangeas also thrive in pots or tubs – provided they have enough space. They should be repotted approximately every two years , ideally in early spring. Use fresh, slightly acidic soil and ensure good drainage.

Potted hydrangeas can also be placed on balconies or terraces during the summer months . It's important to consider the same location requirements as for garden hydrangeas.

How to properly overwinter hydrangeas in pots:

• Never leave potted hydrangeas outside – risk of frost damage to the root ball
• Overwinter in a frost-free but cool place (e.g. garage, conservatory or garden shed)
• Water lightly occasionally so that the soil does not dry out completely

We hope this article helps you keep your hydrangeas healthy and beautiful. In our new Knowledge & Tips section, we will regularly publish new articles on care, varieties, pruning, and color changes.

🌸 We wish you lots of joy in the garden
Your team at Hydrangea World Ullmann