Hypericum ascyron
πŸƒleaf (3)
🌸flower (5)
🍎fruit (1)
🌿habit (1)

Hypericum ascyron

Giant St John's wort Β· Great St Johnswort Β· Great St. Johnswort

Tier 1 Difficulty: easy Water: low Light: full_sun
Temperature
5–35 Β°C
Soil pH
5–7
Hardiness
Zone 4–9
Click count
50
Observations
28

Description

Source: leafsnap

Hypericum ascyron, the great St. Johnswort or giant St. John's wort is a flowering plant in the family Hypericaceae.

🌳 Creeping St. John's wort has a notable but not widely recognized ability to reveal the presence of certain heavy metals in soil. Scientific research indicates that creeping St. John's wort can hyperaccumulate metals such as copper and nickel, making it a possible bioindicator for these elements in contaminated areas. This application is still being researched but highlights the ecological potential of creeping St. John's wort beyond its horticultural uses.

🎭 Unwavering resilience, strength against fear or hostility

Care Guide

πŸ’§ Water

Great St. John's Wort thrives in moist environments, similar to its native habitats near water sources. While it can tolerate moderate drought, it prefers consistent moisture; watering it every two weeks is ideal. This plant is best suited for outdoor settings, making it perfect for rain gardens or areas with varying wet conditions.

FAQ
How should I water my Great St. John's wort plant effectively?

To properly water the Great St. John's wort, it is recommended to use filtered water at room temperature. Tap water may contain harmful particles, so filtered water is preferred. It is important to use water that is at or slightly warmer than room temperature, as the plant is accustomed to a warm environment, and cold water can be a shock. Avoid watering from above, as this can cause problems with the foliage. Instead, gently pour filtered room temperature water onto the soil until it is fully saturated. This helps moisturize the roots and allows them to spread and absorb nutrients from the soil.

What should I do if I give too much or too little water to my Great St. John's wort plant?

Both overwatering and underwatering can harm the health of your Great St. John's wort, but overwatering is more common. When this plant gets too much water, its stems and leaves may wilt and turn yellow. Overwatering for a long time could also lead to deadly diseases like root rot, mold, and mildew. Underwatering is less likely because the Great St. John's wort can handle drought quite well. However, it is still possible, and when it happens, the leaves will become brittle and brown. It's crucial to notice signs of overwatering early when taking care of your Great St. John's wort. Some diseases caused by overwatering, like root rot, cannot be fixed if you wait too long. If you see early signs, reduce your watering immediately. Also, check the soil quality where your plant is growing. If it drains poorly, replace it with loose, well-draining potting mix. If you notice signs of underwatering, simply water your plant more regularly until the signs go away.

How frequently should I water my Great St. John's wort?

To determine if your potted Great St. John's wort needs water, simply insert your finger into the soil. If the top two to three inches are dry, it's time to water. The same method applies for outdoor plants in the ground. Check the top few inches of soil and if it's dry, water the plant. Typically, watering once a week is sufficient during spring and early fall. However, during hot weather, you may need to water twice or more per week. It's worth noting that mature Great St. John's wort plants can tolerate drought well.

How much water does my Great St. John's wort plant need?

To properly water your Great St. John's wort, don't hold back on the amount of water you give it. Make sure the first two to three inches of soil are dry, then give it a nice, deep watering. The goal is to thoroughly soak the entire soil. You'll know you've added enough water if you see excess water flowing through the drainage holes at the bottom of the pot. If you don't see any water draining, it means you haven't watered it enough. However, be careful not to let water accumulate in the soil as that can harm the plant. On the other hand, if you notice water is not draining well, it could be a sign of poorly draining soil, which is not good for the plant's health. Finally, if the plant is outside, it should receive about 1 inch of rain per week.

How should I water my Great St. John's wort during different stages of growth?

The water needs of the Great St. John's wort change depending on its growth stages. In the first few years or after transplanting, it requires more water due to the energy it puts towards sprouting new roots. These roots need extra moisture to support future growth. However, as the plant matures, it will need less water. Another stage where more water may be required is during the bloom period when flower development utilizes a significant amount of moisture.

β˜€οΈ Light Full sun

Creeping St. John's wort flourishes best in locations that receive ample daylight. A moderate amount of sunlight can also support its vigorous growth. It has the ability to endure in spots with limited light, though this might restrain its progress. Originating from a setting with varied sunlight, intense exposure could be harmful, resulting in burned leaves. Likewise, limited sunlight could result in less blooming and a weaker overall constitution.

Ideal: Full sun
FAQ
What kind of sunlight does Great St. John's wort need?

Great St. John's wort needs full sun every day, with a minimum of six hours of sunlight to keep its leaves, roots, and blooms healthy. While most perennials also require six hours of sunlight per day, the Orange Daylily or Giant Coreopsis can survive on as little as three hours of sun. However, these plants won't thrive as well in less sunny conditions as they would in full sun.

Can the sun cause harm to Great St. John's wort? How can we keep Great St. John's wort safe from damage caused by the sun and heat?

In warm climates, some Perennial Flowering Plants may struggle with excessive heat and suffer from sun damage. They can wilt, dry out, or even experience growth problems if they are consistently exposed to the intense afternoon sun. However, not all plants require protection from the light afternoon sun. For those that are harmed by intense afternoon exposure, it is recommended to provide them with some shade in warmer climates. Gardeners can achieve this by planting these plants in areas that do not receive direct heat during the afternoon, such as under trees or behind bushes.

Do I need to shield Great St. John's wort from the sun?

Certain perennial plants require ample sunlight to reach their maximum bloom. However, in warmer climates, some of these plants actually benefit from less sun. For instance, individuals residing in hotter regions might find it beneficial to shade their flowering perennials during the intense afternoon sun, especially during summer months. Although many perennial flowering plants prefer partial shade in the hottest climates, there are exceptions. Take the Giant Coreopsis, for example, as it is not bothered by excessive sun exposure. These plants can flourish even when placed in the full sun during scorching weather.

What will happen if Great St. John's wort doesn't get enough sunlight?

If your Great St. John's wort isn't getting sufficient sunlight, you'll see signs that it lacks what it needs to thrive. In this case, the plants won't yield as many blooms as they would with ample sun exposure. Some plants may even develop dry spots on their leaves, but most will still manage to bloom despite the inadequate sun. However, these flowers will be smaller and less abundant.

Does Great St. John's wort need extra attention to sunlight at different growth stages?

Great St. John's wort is a wonderful flower for gardens. It thrives with at least six hours of sunlight per day, but it can benefit from some shade during the hottest parts of the day to maintain its freshness. When the plant is young, it's important to give it enough sunlight while protecting it from intense afternoon heat. However, once the plant is fully mature, it requires ample sunlight to continue growing properly.

🌑️ Temperature 5–35Β°C

Creeping St. John's wort naturally thrives in climates with temperatures that oscillate between 41 to 95 Β°F (5 to 35 ℃). To promote ideal growth, aim to uphold this temperature range. As the seasons change, adjust appropriately so as to avoid excessively high or low temperatures.

Ideal temperature: 5–35Β°C
FAQ
What temperature is best for Great St. John's wort?

The best temperature for Great St. John's wort depends on the time of year. Let's talk about the two main seasons: the growing season and the dormancy season. During the growing season, when the plant is sprouting, the ideal temperature range is 65-80℉ (18-27℃). If it gets colder than 15℉ (-10℃), the plant might struggle, with leaves browning and wilting. However, if it's just a short cold snap, Great St. John's wort can survive with some help. In the warmer parts of the year, the plant needs protection from extremely high temperatures. Anything above 95-105℉ (35-40℃) can harm the foliage and blooms. High temperatures can cause wilting, drooping, and even sunburn on the leaves, making it hard for the plant to recover. Fortunately, there are quick and easy ways to combat this issue!

The temperature needs for young Great St. John's wort plants in their first year.

If you are planting a new Great St. John's wort, especially if it's the first year, it will require extra care during the coldest months. Frost can be particularly damaging to a young plant like this and may prevent it from growing back in the spring. To protect it, make sure the temperature stays above 40℉(5℃) by either bringing it indoors for a month or two, or using mulch or fabric barriers to shield it from frost. It's also a good idea to plant it in a shadier spot during the first year or two, as smaller and weaker plants have a harder time regulating their temperature in the heat. Limit sun exposure to no more than five hours per day, especially if the temperature rises above 80℉(27℃). To keep it cool in the summer, use shadecloth and water or mist it frequently.

How do I keep Great St. John's wort safe from very hot or very cold temperatures?

During the growing season, if temperatures drop below 15℉(-10℃), there are measures you can take to protect Great St. John's wort from frost or cold damage. If you're growing it in a container, simply bring it indoors with bright, indirect light until temperatures rise above the lower threshold. For ground-planted Great St. John's wort, use mulch or horticultural fabric to create a barrier around the plant to shield it from frost and cold wind. In hot temperatures above 80℉(27℃) during the day, be cautious with sunlight exposure. Limit Great St. John's wort to six hours or less of sunlight per day, preferably in the morning. Setting up shade cloth or a fine plastic mesh can reduce direct sunlight during the hottest parts of the day. Additionally, installing a misting system can release cooling mist around the plant's base to lower ground temperatures.

Recommended temperatures for the dormant season for Great St. John's wort.

Great St. John's wort needs a certain amount of cold during winter to remain dormant until it's time to sprout. It's important not to sprout too early before the last frost, as this can be fatal to the plant, especially if it has already started growing. Ideally, winter temperatures should stay below 32℉(0℃), but if they rise to 40℉(5℃), it will be okay. In more temperate climates like woodland rainforests, there can be unexpected warm spells during winter which may cause Great St. John's wort to sprout prematurely. In this case, if there's still a risk of frost, you can cover it with clear plastic on stakes to protect the sprout from the cold. This covering can be removed once the danger of frost has passed. Although sometimes Great St. John's wort can sprout correctly without any help, using this method increases the chances of a successful second sprouting.

πŸ’¨ Humidity
Humidity:
πŸͺ΄ Soil 5-7
Soil pH: 5-7
🌱 Fertilizer

Fertilizing Creeping St. John's wort at the right times is vital. Begin fertilization in the early spring and continue it on a monthly basis until the start of summer. The addition of fertilizer aids in creating beautiful flowers and supplies energy during both dormant and active periods of growth.

FAQ
Why should I use fertilizer on my Great St. John's wort?

Fertilization is important for the Great St. John's wort because it provides essential nutrients for the plant's growth above and below the ground. However, the plant's fertilization needs are relatively low, and it can survive without fertilization in some cases. Nonetheless, annual fertilization can greatly benefit the plant, helping it to thrive and produce better, longer-lasting flowers. Therefore, those wanting their Great St. John's wort to look its best should prioritize regular fertilization.

When should I fertilize my Great St. John's wort plant?

The best time to fertilize a Great St. John's wort is in late winter to early spring when it is transitioning from its dormant phase to a phase of active growth. Fertilizing during this time promotes healthy growth and sets the plant up for a successful season. Although early spring is generally the most beneficial, fertilizing in the fall is also acceptable. However, it is not recommended to fertilize during summer or winter.

When is the best time to not fertilize my Great St. John's wort plant?

To properly care for your Great St. John's wort, it is important to know when to fertilize. Late winter and early spring are the only suitable times for fertilization, as this plant has low fertilization needs and one annual feeding is sufficient. Overfertilization can occur if you continue to fertilize throughout spring, summer, and fall, so it is best to avoid it during these seasons. However, if you skipped fertilizing in spring, it is acceptable to feed the plant in fall. Additionally, it is unnecessary to fertilize during winter when the Great St. John's wort is in a dormant growth phase and not producing new growth. Therefore, fertilizing during most of the winter is not recommended.

What kind of fertilizer does my Great St. John's wort plant need?

To successfully fertilize a Great St. John's wort, it is generally recommended to use a balanced general-purpose fertilizer containing all three main plant nutrients. However, there are specific nutrient blends that can be even more advantageous. Some gardeners believe that higher levels of phosphorus can result in stronger roots and better flowers, making a phosphorus-rich fertilizer a good choice for Great St. John's wort. Whether in granular or liquid form, the important thing is that the fertilizer contains an ample supply of nutrients. Aside from manufactured fertilizers, organic methods such as compost and manure can greatly enhance the soil quality for your Great St. John's wort. By employing these materials, you can create a healthy growing environment for your plant.

How should I fertilize my Great St. John's wort plant?

To fertilize a Great St. John's wort, the most common method is to use granular or pellet fertilizer. It's important to fertilize when the plant is transitioning from its winter dormant phase to active growth, usually in early spring when shoots start to emerge from the soil. If you prefer liquid fertilizer, you should dilute it with water before application. Whether using granular or liquid, it's always recommended to moisten the soil before, during, and after fertilization.

πŸͺ΄ Pot & Repot
βœ‚οΈ Pruning

Great St. John's Wort is a hardy perennial known for its bright yellow flowers. For bushier growth and better blooms, prune the plant from early to late spring. Be sure to remove any dead stems and shape the plant to improve air circulation. This will help reduce the risk of disease and encourage vibrant flowering.

🌿 Propagating
πŸ› Diseases & pets
☠️ Toxicity

Characteristics

Plant Type
Shrub
Life Cycle
Perennial
Genus
Hypericum
Family
Hypericaceae
Hardiness Zone
4-9
Mature Height
91 cm
Mature Spread
0.91 m to 2.13 m
Leaf Color
Green
Leaf Type
Evergreen
Flower Color
Yellow
Flower Size
3.05 cm to 5.08 cm
Bloom Time
Early summer, Mid summer
Planting Time
Spring, Autumn
Harvest Time
Mid summer
Native Area
Croatia, Bulgaria, Turkey

Tags (7)

Common Names (3)

en Giant St John's wort
en Great St Johnswort
en Great St. Johnswort