Growing Haskaps
Climate and Growing Region
Haskaps are very cold hardy, ideal for northern states. The varieties we offer are more resilient to fluctuating spring temperatures, so they can be grown in areas with more moderate winters and early spring weather. If you are in Zones 2-7, you can grow haskaps. If your climate is warmer, you will need to take extra care to keep them well-watered in the hot summer months.
In warmer zones with hot summers haskaps can drop their leaves after the harvest is finished. In cooler areas they may not drop their foliage until fall, but will not look as green late in the season. However, during this time the plants are increasing their root systems and developing new buds for the following season.
Making a Plan
Before you order plants, you should take some time to develop a plan, which will include: site selection and preparation, layout of the plants in the field, watering system, bird protection, access for harvesting, and last but not least – markets for your crop.
Selecting and Preparing Your Site
The ideal site may depend on your location, but in general choose a site that gets full sun. If your area is very windy, consider planting them in a sheltered area or behind windbreaks to prevent fruit drop on windy days.
Haskaps are adaptable to most soils but grow best on fertile, well-drained soils that are high in organic matter. They can be grown in a wider pH range than blueberries, but prefer a slightly acidic soil. Amending the soil with compost or manure will be beneficial, especially if your soil is heavy clay or sandy. Soil sampling will be helpful in determining the acidity and presence of nutrients.
Before you plant, your area should have good weed-control, including removal of perennial weeds. Summer fallowing the area during the prior season is advised. Here we prepared the area for a season, then laid out the rows with plastic mulch in September. This had the effect of suppressing more of the weeds that were still germinating. Then we planted into the plastic in the late fall.
Planting
We recommend fall planting if possible. The plants will appear to be dormant when you receive them, but they will send out feeder roots and get established before the ground freezes, and then wake up with your ground in late winter or early spring. Timing is critical in very cold climates: plants need a minimum of six weeks from the time they go into the ground until the ground freezes permanently for the winter.
Spring planting should be done as early as possible, as soon as the ground thaws and the days begin to warm up. Don’t wait until the last frost dates, as the quick warming at that time could stress the plants before they get established. You may want to prepare your ground in advance, so that when you receive the dormant plants you can put them straight in.
We space the plants 4 feet apart in the rows, with rows that are 9 feet apart. The spacing between the rows will need to allow your cultivating and mowing equipment to pass through the mature orchard, when the plants could be 4 or 5 feet wide. How you prune your plants will be a factor in the spacing – we do a lot of side-cutting to keep the plants upright.
New plants can be set a couple inches deeper than their original depth to compensate for possible frost heave, and to encourage more root growth.
Watering
Regular watering is necessary to establish and maintain a good root system. Water deeply, but let the soil dry between watering to encourage the roots to grow down and not stay shallow. When the plants are older they are somewhat drought resistant, but if the soil type is one that does not retain moisture in the summer, continued watering will improve crop yields. Discontinue irrigation in the fall to encourage dormancy.
Drip irrigation is efficient, and will keep the fruit in better condition than overhead sprinkling.
Bird Protection
Birds, especially waxwings, love haskaps and can eat or knock off most of the berries in no time. Netting is the most effective means of protecting your crop. Choose material with spaces no larger than 1/2 inch to keep birds from getting their heads stuck.
Our orchard is protected by netting on an overhead trellis system. The netting is rolled up on the frame until the berries begin to ripen, and then we bring down the sides and tuck the bottom edges under lengths of water pipe.
Other deterrent or scare systems, such as acoustic, wind-twirlers, etc. may be helpful in a home garden, but are not very effective in larger plantings. Many mornings we will have hundreds of birds sitting on the roof of our netting peering down longingly. Birds have nothing else to do all day except try to figure out how to get into your haskap orchard!
Maintenance
In our field we laid 1-ml black plastic for the rows, with a drip irrigation line underneath. After planting into those rows, we left the plastic for 2 years. It became a bit ragged in time but still did a good job of suppressing weeds. In year 3 we carefully collected all the plastic and applied composted chicken manure, then covered that with at least 6 inches of leaf mulch. After the leaf mulch was applied with a side-chute spreader, we walked the rows and by hand pulled excess leaf mulch a bit away from the base of the plant, making sure to free any buried shoots. An application of mulch each spring has kept out most weeds except creeping grasses. We go through with hoes twice per year to prevent the few weeds from going to seed, but because the leaf mulch is thick, the annual weeds hoe out very easily. Creeping grass can be a problem if you only use a hoe.
Between the rows we use a low growing grass and mow it. The issue with grass between rows is that there will be a 6-week period during peak grass-growing season when you will not be able to mow, because 1) your bird-netting is in place, and 2) you will not want to knock fruit off the plants.
No significant diseases or pests have been noted, except for birds. In our area, some varieties are prone to powdery mildew on the leaves in late summer and fall as the plants are entering dormancy. This doesn’t seem to affect the overall health of the plants in the next season.
Harvesting
Haskap berries are ready to be harvested at around the same time as strawberries. They will look ripe one or two weeks before they are sweet enough to eat. Some fruit will begin to drop as they ripen, and some varieties (but not all) will turn from green to red/purple inside when ready. Testing for sweetness (Brix) with a refractometer is the best way to determine the correct time for harvest. Japanese varieties are generally ready to be picked when they reach a Brix of 15.
Haskaps are labor intensive to hand pick, and the more efficient harvesting techniques use some form of shaking with a catch-basin. There are a good number of ideas available on YouTube, from very basic to more sophisticated systems. Commercial growers could consider an adaptation of a mechanical harvester.
A 5-year-old plant should yield 6 to 10 lbs of fruit.
Pruning
Annual pruning should begin when the plants have been in your ground for three years. (Before that time simply remove damaged or weak wood.) This should be done in late winter or early spring, before the buds begin to swell.
As berries are produced on one-year-old wood, you should remove some of the older branches each year to stimulate growth of new wood for future years. Shape the plant to keep the interior open, and take out any wood that looks unhealthy or weak. You can take out up to 25% of the plant, but more than that will affect yields negatively.
If you grow blueberries or currants you will have an idea of how to prune, but practice and note-keeping will help you learn. We are still experimenting with various pruning techniques, with the goal of increasing berry size and yield.