For hydrangeas to change from pink to blue, the soil must be acidic and contain salts of either aluminum or iron.
We all learned in chemistry classes in school that distilled water has a neutral pH of 7. However, in horticulture, a neutral pH is typically categorized as 6.5. Any soil with a pH below 6.5 is considered acidic, and any soil with a pH above 6.5 is considered alkaline. A pH testing kit can be used to check the pH of your soil, and Greenshutters Nurseries & Garden Centre has these on hand. The inexpensive pH meters that are available are often not precise, so I do not advise using them. Often, seeing surrounding gardens and the local plant life is a simpler approach. It’s likely that your soil is acidic if nearby Rhododendrons, Camellias, and Pieris are flourishing in the soil.
Peaty or sandy soils are typical of acidic soils. Clay soils are typically not highly acidic. Chalky soils have a high pH. By incorporating Irish moss peat or ericaceous compost, you can increase the acidity of your soil. Ericaceous compost has an acidic pH range of roughly 5.0 to 5.5, while regular multifunctional compost has a pH range of 6.0 to 6.5.
Irish moss peat is particularly useful for mulching since it has a pH of about 4.0, which is much too acidic for most plants to thrive in. However, when combined with neutral or alkaline soil, it lowers the pH of the soil. Once a year, mulch with Irish moss peat and let the worms to work the peat into the soil to maintain the acidity of the soil around a plant.
As an alternative, hydrangeas can be grown in containers. Although hydrangeas can thrive in both multifunctional and ericaceous compost, it is recommended to plant them in the latter if you want them to turn blue.
If your soil is deficient in aluminum or iron salts naturally, you can easily increase them by putting Hydrangea Colorant into the soil. People claim that adding rusty nails to the soil or compost will turn hydrangeas blue; however, as I have never tried it, I am unable to confirm if this is true or false. On the other hand, Hydrangea Colorant is a combination of Iron Salts and Aluminium Sulphate. When potting or planting, it can be added to the soil. For established plants, you can also dissolve the Hydrangea Colorant in water and give your hydrangeas a weekly drink during the growing season (March to September). Your light pink kinds will become blue if you do this, while your dark pink varieties will turn mauve-blue.
Grow your hydrangea in neutral or alkaline soil, though, if you want it to stay pink.
Which compost kind is ideal for hydrangeas?
According to John Negus, a garden expert for Amateur Gardening, “the ideal potting compost for shrubby plants is one with a high concentration of loam, such as John Innes No. 3.” The RHS (opens in new tab) suggests combining two parts of John Innes No. 3 and one part peat-free multipurpose compost for hydrangeas. Use an ericaceous compost as an alternative if you are growing blue hydrangeas and want to maintain the vibrancy of their color.
Even the best multi-purpose composts, according to John, “only have adequate nutrients for four to six weeks of growth, and after this is expended, plants will need supplemental feeding, either with a liquid or by top-dressing with controlled-release fertilizer.” From early summer to the end of flowering, feed with a liquid or top-dress in the spring.
John continues, “Loam-based composts retain moisture better than peat-based ones.” All potted plants, however, require constant watering because their roots are restricted and their compost is hidden by foliage, unless it rains heavily every day.
Any plant may I use ericaceous compost on?
Compost that is specifically designed for growing ericaceous plants is an acidic sort of compost. These can include plants that do poorly in alkaline soil, such as heathers (the word “ericaceous” is derived from the Latin word for heathers), camellias, and rhododendrons.
Can you fertilize hydrangeas with compost?
We use the word “influence” since using lime or acids rather than compost is more common when adjusting soil pH to change the color of bigleaf hydrangeas. Composting your planting bed has kinder and healthier impacts than using powerful additives to make abrupt pH alterations.
Additionally, hydrangeas adore the rich, wet soil that compost produces. You have probably observed that hydrangeas require a lot of water each week. Your hard clay soil’s ability to hold moisture is improved by soil3.
Bigleaf hydrangeas come in both blue and pink varieties, and most gardeners are content with whatever color the soil pH produces. The health of your hydrangeas is the primary priority. By incorporating compost, you may enrich and care for the soil that supports your favorite hydrangea shrubs, allowing it to support the healthiest hydrangeas you’ve ever grown.
Read the Soil3 Story: Creating Hydrangea Heaven with Soil3 Compost to see how Drte Schmieta uses Soil3 in her hydrangea garden.
A client who lives close to our Orangeburg, South Carolina, farm emailed these photos of his prized hydrangea flowers, which he planted in a garden bed with Soil3. Because Soil3 neutralized the soil, you can see how some of them have taken on a reddish hue. He has every right to be proud of his Hydrangea macrophylla (also known as bigleaf hydrangeas), and we appreciate him sharing that pride in both our compost and his plants.
Which vegetation can be grown in ericaceous compost?
You want to plant some flowers that need an ericaceous compost, but you have no idea what that word means or what it does. You’re surely not the only one who thinks so, though!
There are quite a few plants that, for a variety of important environmental reasons, can only flourish in this kind of compost. That is to say, you might be setting yourself up for failure if you try to produce Camellias, Blueberries, or Heather before first determining your soil type.
Nevertheless, don’t panic! We have all the details you require about ericaceous compost and how it will benefit particular plants in your yard.
What is ericaceous compost?
The plants that like to grow in it gave the soil type ericaceous, which is more acidic, its name. The Ericaceae family is the name given to them. This indicates that in order to support their growth, these acid-loving plants require a more acidic compost. Ericaceous plants are also referred to as lime-hating plants since they do not thrive in soils that are high in alkalinity.
Which plants need an ericaceous compost?
Rhododendrons, Azaleas, Camellias, Hydrangeas, Holly, Fern, Gardenia, Aster, Magnolia, Pachysandra, Lupine, Pieris, Viburnum, Bleeding Heart, Japanese Maple, Juniper, Blueberries, Raspberries, and Cranberries all require an ericaceous compost to aid in growth. There are many more, so be careful to investigate the kind of compost your plant need!
Why do these plants need ericaceous compost?
Ericaceous plants generate yellow leaves when grown in alkaline or lime soil. Chlorosis brought on by lime is the medical term for it. They typically die because they don’t grow or blossom well. The primary cause of this is that they require iron and other soil nutrients, which become insoluble or “locked up” in the soil when the pH is high and prevent the plants from absorbing them.
It could be simpler to cultivate these plants in pots or tubs if your soil is alkaline.
How should I care for and grow my ericaceous plants?
Consider growing your plants in a sizable pot or container that is loaded with ericaceous compost. The container is necessary so that you can later position your plants according to their demands in the appropriate region of your garden.
The majority of Ericaceous plants cannot be in direct sunlight because the exposure will cause their blossoms to turn brown. They are hence ideal for growing in shade.
Make sure to feed your plants with a sufficient fertilizer, and you’ll need a special ericaceous plant feed for the compost. A continuous release plant food is an alternative that can be applied once and nourish plants for six months.
Ericaceous plants also require constant watering, particularly in the summer. Therefore, be sure to water your plants once a week and mulch the soil well to keep the moisture in.
What kind of soil works best for potted hydrangeas?
Because they are such dependable flowering shrubs, hydrangeas are suitable for gardens of all sizes. Compared to most other plants, they flower for significantly longer periods of time—often months as opposed to weeks. Even after they have gone, the blossoms frequently retain their beauty, giving the garden interest even in the dead of winter. They make wonderful cut flowers as well.
They are simple to grow both in pots and outdoors, which is wonderful news. They only require the right environment, lots of water during dry spells, and sporadic feedings with the proper fertilizer, one that is designed to bring out the best in them.
In the open ground or in pots and containers, pot-grown hydrangeas can be planted at any time of year using Vitax John Innes compost. Pick for good, sizable containers that will enable the plants to flourish for many years. Smaller containers soon dry out.
Prepare the soil thoroughly before planting in open ground by incorporating a lot of garden compost or organic manure to strengthen the soil. To increase the humus content of the soil, which aids in water and nutrient retention in subsequent years, a few handfuls of 6X Natural Fibrous Fertilizer should be forked well into the soil.
When planting, mix a few handfuls of compost or Vitax Hydrangea Feed into the soil. This offers all the necessary nutrients for strong growth and lovely blooms.
The majority of hydrangeas may grow in full sunshine, but they prefer light shade. They thrive in dense clay and flourish in most soil types. They are therefore appropriate for the majority of newly constructed gardens and moist, compacted soils. They prefer plenty of water, as implied by their name, thus adding organic compost or organic manure on a regular basis helps retain moisture. Compost or bark mulch applied around the plants early in the growing season when the soil is moist also aids in moisture retention. Do this after they apply Vitax Hydrangea Feed annually.
The most well-known and colorful kinds of Hydrangea macrophylla are mophead and lace cap hydrangeas. Throughout the season, their flowers frequently change color, and the soil might have an impact on the color of some types. Some are blue on neutral to acidic soil and pink in alkaline environments. Use Vitax Hydrangea Colourant, added to the soil after planting or to the growing media in a pot, to preserve the blue color. Additionally, it can be diluted in water and sprayed on mature plants. However, be patient as this should preserve the color. It does not always function right away.
The compact growth of new hydrangea cultivars makes them perfect for tiny gardens. Many of these produce flowers on both the branches developed in the upcoming season and those from the year before. Consequently, they grow more flowers.
The well-known Hydrangea arborescens ‘Annabelle,’ which grows in a clump of tall stems with soft leaves and sizable frothy, white flowerheads, is another superb garden hydrangea. It looks its best when in bloom and provides a stunning spectacle when under the light shadow of trees.
The popularity of Hydrangea paniculata variants is rising. These bloom in the late summer, producing huge, conical flower heads at the tips of the stalks that are reminiscent of lilacs. The majority are white, occasionally with pink or burgundy flushes. They are ideal for the back of a perennial-filled border.
Leave the flower heads on Macrophylla hydrangeas during the winter, and in the spring, prune each stem back to the first pair of fat buds behind the flower. In the case of old, established plants, some of the older stems can be pruned back all the way to the ground in the winter.
Hydrangeas Paniculata: Hard prune in late winter, reducing by half to two thirds. Maintain a sturdy branch framework at the plant’s base. Strong shoots with flowers at the tips are produced as a result.
Hydrangea arborescens: In the late winter, trim all stems to a height of 15 cm (6 inches). Although this may seem severe, it guarantees strong shoots that should remain upright.
Feed by sprinkling Vitax Hydrangea after pruning, or at any time during the growing season. Feed the area around the plants, hoe or fork it into the soil’s surface, and then liberally water. One of the longest-lasting flower displays in the garden will result from your hydrangeas’ wonderful blossoms and leaves.
Are hydrangeas plants that love acid?
Although they can also be cultivated in neutral soil, hydrangeas appear to all favor acidic soil. They can even tolerate somewhat alkaline soil, but if your garden soil has a naturally high pH level, it is best planted in ericaceous soil in containers.
Hydrangeas are typically white, pink, or blue. Acidic soil will cause pink hydrangeas to become blue. On the same bush, you might have a gorgeous dazzling display of pink, lilac, and blue flowerheads.
The greatest places to grow hydrangeas are in regions with high rainfall since they adore water.
Can I use ericaceous compost to plant my rose?
Making ensuring that you have the ideal soil conditions is crucial if you intend to establish a rose garden. What will happen to them if you use an acidic ericaceous compost then?
In soil with a slight acidity, roses will flourish. Between 6 and 6.5 is the pH range that they prefer. As a result, ericaceous compost is a wise option as it aids in raising the soil’s acidity. If the issue persists, try using sphagnum peat or sprinkling some powdered sulfate.
Since roses often like acidic soil, using ericaceous can be advantageous. To find out if it’s a smart idea to apply this kind of compost on your roses, keep reading.
What types of plants dislike acidic soil?
High pH soils are referred to as alkaline soils, and they are typically chalky or limestone-rich.
In the UK, chalk downlands, including places like the South Downs, Chiltern Hills, and Salisbury Plain, are frequently home to these soils. Your soil is probably alkaline if you reside in a region with limestone deposits.
Test your soil pH with a kit at the garden center or online to be sure of its pH.
Alkaline soils shouldn’t be used to grow ericaceous plants since they can’t absorb essential nutrients like iron.
Lily of the valley
Lily of the valley is a good option if you’re looking for a ground cover plant for alkaline soils. There are various lovely cultivars to grow, including “Albostriata” and “Hardwick Hall,” and the flowers have a pleasant aroma.
Phacelia
Phacelia is frequently cultivated for green manure, but it’s worth letting it bloom to see how many pollinators it can draw. It belongs to the same family as many other lime-loving plants like borage, viper’s bugloss, and anchusa, which is called the Boraginaceae.
Ornamental clovers
On calcareous soils, ornamental clovers like Trifolium rubens and Trifolium ochroleucon excel. In actuality, most members of the Fabaceae family of plants detest acidic soils.
Wild marjoram
Origanum vulgare, often known as wild marjoram, is a simple plant to cultivate if given enough sunlight and well-drained soil. Grown cultivars include “Aureum” and “Compactum.” a favorite flower of butterflies.
Polemoniums
The attractive native perennial Jacob’s ladder (Polemonium caeruleum) loves moist, lime-rich soil. Before planting, amend the soil if it is fairly thin by adding a lot of organic matter, such as leaf mold and well-rotted manure.
Sesleria caerulea
Due to the glaucous uppersides of the leaf, this natural, evergreen grass is also known as blue moor grass. Sesleria caerulea will gradually expand if grown in full light.
Lavender
Chalky soils offer free-draining soil, which lavender and other aromatic plants like rosemary, thyme, and artemisia would like. To get the most out of them, grow them in full light.
Honeysuckle
There are many varieties of Lonicera periclymenum, our native honeysuckle, to grow, including ‘Graham Thomas’ and ‘Serotina,’ and it thrives in a variety of environments. excessive honeysuckle? Learn how to prune honeysuckles.
Spindle
Euonymus europaeus, sometimes known as spindle, is a tiny native shrub or tree. Brightly colored fruits are still present to add interest after the leaves have gone, and the autumn colors are breathtaking.