Origin and Common Names
Gunnera makahaensis St. John is a member of the Gunneraceae family and is native to Hawaii. The plant is also commonly known as Hawaiian giant rhubarb or Makaha water plant.Appearance
This plant has large, deeply lobed leaves that can measure up to 6 feet (1.8 meters) across. The leaves are bright green in color and have an almost circular shape. The plant produces tall, fleshy stems that can reach up to 10 feet (3 meters) in height. These stems hold clusters of tiny flowers ranging from brown to reddish-purple in color. The plant's roots are thick and fibrous, allowing it to thrive in wet or boggy soil.Uses
In Hawaiian culture, Gunnera makahaensis St. John has been used for medicinal purposes. It is believed that the plant possesses anti-inflammatory properties and can be used to treat wounds and injuries. Additionally, the plant's large leaves can be used for decorative purposes, such as in floral arrangements or as a backdrop in landscaping. Despite its resemblance to rhubarb, the plant is not edible and should not be ingested.Light Requirements
Gunnera makahaensis St. John grows best in partial shade to full sunlight. In its natural habitat, it often grows under the canopy of trees or alongside water sources that provide shade. If grown in full sunlight, it may require more frequent watering to prevent the soil from drying out.
Temperature Requirements
Gunnera makahaensis St. John thrives in warm weather, with an optimal temperature range of 18-25°C (64-77°F). It can tolerate cooler temperatures down to 4°C (39°F), but growth may be stunted. Extreme heat above 30°C (86°F) can also be detrimental to its growth.
Soil Requirements
Gunnera makahaensis St. John prefers well-draining soil that is rich in organic matter. It can tolerate a wide range of soil types, from sandy to clay soils. The ideal soil pH is between 5.5 to 6.5, which is slightly acidic. It requires consistent moisture, but the soil should not be waterlogged or overly saturated, as this can lead to root rot.
Cultivation Methods
Gunnera makahaensis is a fascinating plant that thrives in moist soil. It is best to grow it in an area that receives partial to full shade. When planting, make sure to use well-draining soil, and the recommended spacing between each plant is about 4-5 feet apart. This plant does well in zones 9-11, and the ideal temperatures are between 50-75 degrees Fahrenheit.
Watering Needs
Gunnera makahaensis needs ample water to thrive. Make sure the soil is moist and not waterlogged. You can water the plant once or twice a week, depending on the weather conditions. When watering, ensure that the foliage and the roots are soaked completely. For optimal growth, it is ideal to use rainwater or tap water that has been allowed to sit overnight.
Fertilization
This plant is not too demanding when it comes to fertilization. However, you can use organic fertilizers such as compost and well-rotted manure during the growing season to promote healthy growth. You can apply the fertilizer every month or two by spreading it generously around the plant. Avoid getting the fertilizer too close to the plant's stems or foliage, as this could cause damage.
Pruning
Gunnera makahaensis does not require pruning, but you can remove any dead or damaged foliage to improve the plant's appearance. Removing the brown leaves allows new leaves to grow and helps prevent the spread of diseases. When cutting the leaves, ensure that you use clean and sharp tools to prevent damage to the healthy plant parts.
Propagation of Gunnera Makahaensis St. John
Gunnera Makahaensis St. John, commonly known as Hawaiian giant rhubarb, is a perennial plant that is native to Hawaii. It is a remarkable plant that can add a stunning focal point to any garden. Propagating Gunnera Makahaensis St. John is an excellent way to produce more plants for your garden. This plant can be propagated by three methods: seed, division, and cuttings.
Seed Propagation
Gunnera Makahaensis St. John can be propagated from seeds, but this method is not commonly used because the seeds have a low germination rate. The seeds should be planted in a well-draining potting mix and kept in a warm, humid environment. Seedlings can take up to two years to develop, and they require regular watering, fertilization, and repotting as they grow.
Division Propagation
The most common method of propagating Gunnera Makahaensis St. John is by division. This method involves digging up an established plant and separating it into two or more smaller plants. The best time for division is in the spring when the plant is actively growing. Care should be taken not to damage the plant's crown and root system. The new plant should be placed in a suitable location with good drainage and ample sunlight.
Cutting Propagation
Gunnera Makahaensis St. John can also be propagated by taking cuttings from the plant's rhizomes. This method is commonly used to produce new plants quickly. Cuttings should be taken in the spring or summer when the plant is actively growing. Cuttings should be about 6 inches long and planted in a well-draining potting mix. They should be kept moist and warm until they develop roots. It usually takes about 2-3 weeks for the cuttings to root.
In conclusion, Gunnera Makahaensis St. John is an attractive plant for any garden, and propagating it is an excellent way to produce more of these lovely plants. Seed propagation is not commonly used, and division and cutting are the most popular methods. Care should be taken to ensure that the new plants are placed in a suitable location and given proper care to thrive.
Disease Management
Gunnera makahaensis is generally resistant to pest and disease, but under certain conditions, it can develop some ailments. One of the most common diseases that affect the plant is fungal diseases, which can cause leaf and stem browning, wilting, and eventually plant death. To manage fungal diseases, remove any infected plant parts, avoid overhead watering, and apply fungicide as necessary.
Bacterial diseases can also attack Gunnera makahaensis and can cause leaf spotting, wilting, and stunting. There is no cure for bacterial diseases, so the best approach is to remove the infected plant parts, disinfect garden tools, and avoid overhead watering.
Viral diseases can cause mosaic patterns on leaves and stunt plant growth. Unfortunately, there are no known treatments for viral diseases, making prevention the best option. Avoid planting healthy plants next to infected plants and controlling insect populations in your garden to reduce the spread of viruses.
Pest Management
The most common pests that attack Gunnera makahaensis are slugs, snails, and aphids. Slugs and snails can cause significant damage to leaves, and aphids cause leaf curling and yellowing. To manage these pests, apply a slug and snail bait around the perimeter of the plant, and use insecticidal soap or neem oil to control aphid populations.
Caterpillars and beetles can also cause damage to Gunnera makahaensis leaves. Physical removal of the insects, handpicking them or using traps, can be effective in controlling populations. For larger infestations, apply insecticide as necessary, following label directions carefully.
Finally, spider mites can cause leaf yellowing and webbing on the plant. Use a strong stream of water to physically remove as many spider mites as possible, or try using an insecticidal soap or neem oil to control populations.
