Here are other thoughts and suggestions based on our experience as small-scale, part-time growers in the upper Midwest —
Choose the site for your elder plants with care. A sunny, fertile site that stays slightly on the damp side is ideal. Avoid dry upland locations, low-lying boggy areas, or overly shady sites. If you have an area in full sun where grass usually grows lush and green, that might be a prime spot for elderberries.
Elder prefers soil with the ability to retain moisture and nutrients yet still drains well. Good soil types would be silty-loam or clay-loam soils rather than sandy soil or heavy clay.
If you live in the right climate and carefully choose the location for your elder orchard, irrigation may only be needed for young plants. We irrigate plants for the first couple of years using inexpensive soaker hoses from the hardware store. We do not irrigate mature plants.
Some growers in warmer regions of North America are skeptical that elderberries can thrive without supplemental irrigation, but we are not the only growers in the upper Midwest who do not irrigate and get good results. Growers in hotter or drier climates or those with sandier, drier soils, however, may need to install permanent irrigation systems for elderberry to thrive.
Two year old plants in rows spaced 14 feet apart. It seems like there is plenty of room between rows at this age, but that will change as time passes.
We space rows about 14 feet apart and have sometimes debated whether a 16 foot spacing between rows would be better. A 14-16 foot spacing might seem overly generous to the inexperienced eye, but remember elderberry plants spread a lot as they mature.
Leave aisles wide enough so you can get a riding mower, small tractor or ATV, and other equipment between rows with minimal damage to the canes. Other benefits of a generous aisle width are maximizing the sunlight that reaches the plants and encouraging air movement for disease control.
3-4 year old elder plants planted 2 feet apart within the row. Rows are spaced about 14 feet apart. These older bushes shade a lot of the aisle. As berries develop, the canes will be weighed down and spread even more.
We space our plants 2 feet apart within each row. As the plants mature and spread, they will form a nearly continuous line of plants along the row. This discourages a lot of weed growth within the row.
Newly transplanted elder plant (center) in a row mulched with paper (brownish purple at top center) and coarse wood shavings. We will add a layer of old hay or bark mulch over the shavings.
Mulching around young plants is absolutely a requirement. Mulch controls grasses and other weeds that will otherwise stunt or kill the small elder plants. Mulch also keeps the soil cooler and moister to reduce the need for irrigation and minimize stress on young plants.
Some growers use plastic sheeting or plastic weed barrier as mulch. We have been using a continuous layer of paper mulch on either side of the elder plants to smother young weed seedlings. We have used heavy commercial paper mulch that comes in large rolls or thick layers of recycled newspaper sheets or a combination of both.
We will sometimes cover the paper mulch with a layer of coarse wood shavings (sold in large bales for animal bedding) for short term protection and to fill in any gaps in the paper.
The wood shavings are not strictly necessary, but they are easy and light enough to quickly scatter over and around tender young plants as we plant. Unless the weather is really windy, the shavings will hold the paper in place for a day or two until we have time to add the heavier hay or bark mulch.
A generous layer of old hay or bark mulch is applied over the shavings for longer lasting weed control and better protection from wind.
When finished, the mulch extends 1 1/2 to 2 feet on either side of the elder plants. That allows us to mow safely along the edge of mulch without damaging the plants.
First year plants protected with paper and hay mulch
We renew the hay/bark mulch every year for the first two or three years. As elder plants become taller and more lush, they will shade out all but the worst of the weeds and further mulching is not strictly necessary.
Regular mowing along the aisles, hand weeding within the rows, and perhaps some careful spot applications of herbicide do a pretty good job of controlling weeds in a mature planting.