Common Harvesting Methods For Sea Buckthorn
In 2009, I embarked on a comprehensive study of the diverse sea buckthorn cultivars found in our region and across the globe. This journey led me to a remarkable opportunity to learn from the president of the European Sea Buckthorn Association, a seasoned expert with a profound understanding of sea buckthorn. His extensive knowledge has been instrumental in developing many of the cultivars we know today, including the varieties I promote.
The years of practicing his teachings have led me to try many different ways of propagating and harvesting sea buckthorn. During this time, I’ve shared much of my knowledge of the growing fundamentals with my readers, which has led to some reaching out with specific questions. Some of the most frequently received questions and concerns involve proper pruning and harvesting techniques for sea buckthorn shrubs. The truth is there are several known methods for harvesting sea buckthorn. Some use hand-held tools with wire, while some harvesters in Mongolia wait for the branches to freeze during the cold nights and smack the berry-laden branches with sticks to knock them off. However, to provide the most practical knowledge, I’ve decided to share the methods used by commercial growers across Europe, where the sea buckthorn industry has thrived for decades.
Pruning sea buckthorn for optimum health and yield.
Maintaining a well-pruned sea buckthorn orchard offers a multitude of benefits. The response of your plants to regular pruning, which largely depends on the species, subspecies, and variety, can significantly enhance their health and yield. The primary objectives of pruning in commercial orchards are to regulate size, shape, and height for efficient fruit harvesting, optimize light exposure for superior fruit growth, and manage the ideal number of new fruit-bearing branches. Regular pruning also promotes the overall health and vigor of your plantation by removing dead or broken branches.
Regular maintenance pruning is crucial to sea buckthorn cultivation, starting as early as the first year of planting. Pruning should be carried out with the understanding that all branches will need to be replaced over a 3-4-year period, underscoring the ongoing commitment required for the health and productivity of your shrubs.
It’s best to perform the first-year prune before bud break in late winter or early spring, combining topping, thinning and shortening cuts. This trim will stimulate vegetative growth, so you need to be careful with your cuts, as overcrowding of branches is a major factor in low fruit yields, partly due to the low amount of light penetrating the inner branches. It’s better to make a few large cuts than many small ones. A pruned branch should be smooth and angled to encourage the healing process and prevent disease. Well-maintained pruning shears and saws are essential for efficient, clean pruning. For the best phytosanitary protocol, tools should be cleaned after pruning each plant and sharpened regularly.
The general method for harvesting sea buckthorn berries at a commercial scale is to strategically cut fruit-bearing branches from one year to the next to the optimum height for harvesting, which is between 1.5 and 2.5 m (5-8′). Then, freeze the berry-laden branches while still on the branch. Finally, a simple vibration will easily remove the berries from the branch once the fruit is frozen. A machine generally does this last step with lasers to selectively remove damaged or underripe fruits.
Baltic commercial growers most often use the “lower cut” or modified leader method to harvest sea buckthorn. With this method, plants are topped at a height of 60 cm (~2′) after the first year of planting, resulting in the formation of several angled, straight and narrow branches. The top shoot becomes the central leader during the first growing season. At the end of the second year of growth, all branches shorter than 30 cm (12″) above the ground should be cut back. All other branches are cut back only to maintain a taller central leader. When harvesting, small, weak branches are selected first. These are located in the lower inner parts of the tree. Branches whose diameter exceeds 50% of the diameter of the leader are then removed. If the upper shoots are left untouched, the main trunk will have to be cut sooner or later to form a new shrub with many branches.
The modified leader harvesting method ultimately leaves a shrub that needs regenerative pruning to form new branches. This regenerative cutting is carried out in late winter or early spring when plants are recovering best as carbohydrates still stored in the lower parts of the tree begin to circulate upwards after coming out of winter dormancy. If this operation is carried out in September, these essential nutrients are cut off at the same time as the upper branches. The main disadvantage of the lower-cut method is that radical cutting of the main trunk results in two empty years before the tree is reconstituted for a full harvest for another 4 years.
In an attempt to improve on the failure of the previous method, pruning was adapted to create two equal sections within the tree with a one-year age difference between the sections. This is known as the Vertical Splitting Method (see image for a visual description of this method). Vertical splitting has the advantage of less maintenance pruning and better light penetration for better fruit production, and the tree naturally retains the best height for hand harvesting. All branches on the harvesting side must be cut back, so one year in three is not productive when this method is used. The shrub rejuvenates gradually, avoiding a long break in harvesting years. However, this method can only be used in well-planned and maintained orchards because a shrub won’t regenerate the removed branch if it lacks nutrients, water, or sunlight.
Example of the horizontal split method of growing and harvesting sea buckthorn.
Another method European growers use is the horizontal splitting method, which was created for small home gardeners. In early spring, annual shoots are bent downwards, with the tops fixed to the ground. The fruits attach themselves to the bent branches, while new vegetative shoots develop directly from the upper points of the arch, this being due to the accumulation of growth hormones as a result of positive geotropism. The lower parts of the branches are harvested in autumn, while the new shoots remain intact until the following spring when it’s their turn to be bent. The horizontal splitting method is very gentle and produces a beautiful plant. In some cases, it can increase yields, but above all, it avoids barren years. Nevertheless, this method is very labour-intensive, and when there are several hundred shrubs in a plantation, it can become costly in terms of workforce.
Finally, according to the book Sea Buckthorn (Hippophae Rhamnoïdes L.): Production and Utilization, written by Thomas S.C. Li and Thomas H. J. Beveridge, sea Buckthorn can give good results with the open-center system. At planting, shrubs are pruned to about 60 cm (24″), and all buds within 30 cm (12″) of the ground are removed. Trees are trained in a multi-branched system, with the main branches extending upwards and away from the trunk, resulting in a vase-shaped tree. At the end of the second year, all newly developed branches within 30 cm (12″) of the ground are removed. Next, the potential central leader is removed, the head is cut back, and all branches are thinned to maintain the desired height.
In short, it is important to pay attention to the common principles of pruning and harvesting sea buckthorn by selecting methods that align with the scale of your project. But remember, practice makes perfect, and if you make a mistake, chances are you can make up for it later. A healthy sea buckthorn shrub regenerates easily. It just takes some time.
