Griselinia Hedge Problems

A hedging species native to New Zealand, the Griselinia Littoralis has grown vastly in popularity in recent years, now becoming one of the most popular hedges in the UK. As an evergreen shrub, it not only guarantees green hedging all year round, but also offers attractive yellow-green flowers in the spring, followed by purplish small fruits during autumn on female plants. One of the most recognisable characteristics of griselinia hedges are their beautifully simple oval leaf shape that gives the plant a bushy appearance that one might not find with other types of hedging.

If you are considering purchasing a griselinia hedge, you may be concerned about problems that you may encounter in the future. However, you need not worry too much, as this plant species is a true ‘all rounder’. It can also be planted in a variety of common soils, including chalk, clay, sand and loam. Here are some griselinia hedge problems you may encounter.

Pests & Disease

A relatively low maintenance hedge, griselinia littoralis is generally pest-free which is good news for gardeners. You will not have to invest in plant medication or other types of preventative measures as the plant’s hardiness keeps it protected from pest damage. Griselinia littoralis is also relatively disease-free, however it can become susceptible to leaf spot.

Leaf spot is caused by the spread of a fungus, which results in unattractive black or brown spots scattered throughout some or many of the plants’ leaves. While leaf spot is common amongst both house plants and outdoor plants, it can be frustrating to deal with, especially if the fungus has spread across the majority of your hedging.

The spread of the fungus generally occurs in a warm and wet climate, when the leaf surface has moisture on it. This gives the fungal spore a place to cling onto, and with warmth it will begin to reproduce or sporulate. With sporulation, a tiny brown spot on the leaf will continue to grow, becoming large enough to touch a neighbouring leaf for the spread to continue. If left untreated, the leaf will continue to brown and darken, eventually dropping to the ground for the cycle to begin once again.

Luckily, leaf spots are relatively easy to prevent. If you are living in a location where you are prone to moisture gathering on your leaves, you can thin out any plant foliate that is gathered tightly. By doing this, you can prevent the further spread of fungus amongst foliage clusters. If you do decide to prune your griselinia, remember to treat your pruning shears and any additional tools with bleach after completing your task to prevent fungus spreading to another plant you prune later. Where possible, it is also recommended to rake up any of the leaf debris from the soil to further lessen the risk of leaf spot spread.

If you have already found leaf spots on your griselinia, there are several methods for removal to consider. In some cases, there may only be very few leaves that have been impacted. This can be dealt with quickly by removing any of them that exhibit signs of damage. However, if your griselinia hedge has been more impacted you can either use organic treatments or fungicides to deal with your leaf spot problem.

For gardeners who prefer organic treatments, you can spray the plant with a mix of bicarbonate soda and water (½ tsp per 4 litres of water). Alternatively, you can purchase other organic treatments from online or your nearest garden store. Please be aware that these may contain sulfur or copper octanoate.

Chemical fungicides are also readily available for purchase from online retailers and in garden stores, however it is recommended that you speak to a professional beforehand to ensure that you are purchasing the right product for your garden.

Root Rot

A common killer of plants is another fungus-like organism. Phytophthora is a type of root rot that exists in soil and can cause the decay of roots in plants if left untreated. This disease occurs as a result of waterlogged soils or very heavy soils where it rots the fine feeder roots and eventually some of the larger roots.

Symptoms of griselinia root rot can be seen when the usually-green leaves become pale or fall out. These symptoms will worsen if left untreated and the plant may eventually die as it cannot take up water properly. You can treat the problem non-chemically, but some treatment options can be more labour intensive than others. Increasing the drainage of soil can be a great preventative measure as the Phytophthora thrives in very wet conditions.

However, if your griselinia hedge has already become impacted with root rot, you may want to consider sending soil samples to a specialist that can identify whether root rot is the actual problem. If it is, you will have to remove any affected plants and replace the impacted soil with fresh topsoil to prevent any further spread. If you choose to replant your hedge, make sure that you do not replace your griselinia with a hedge species that is very susceptible to root rot, such as Buxus, Taxus, Ribes and more.

For more information on griselinia hedge problems, feel free to contact Hopes Grove Nurseries. Alternatively, you can check out our Knowledge Base or our article on how to prune a Griselinia Littoralis hedge. We have extensive knowledge of hundreds of hedging species and offer a variety of plants ready to be added to any garden. You can contact us online or call on  01580 765600 to speak to a member of the Hopes Grove Nurseries customer service team.