Goldenberry

Soil preparation should include a soil test with all nutrients brought to optimal levels. Organic matter should be above 3.0% if possible. An initial nitrogen addition of 50 pounds of nitrogen per acre is recommended pre-planting.

For high tunnel production, plants can be grown from seed, sown indoors in late winter with adequate light to avoid tall, stretched seedlings. Plants, when at least 6 to 8 inches tall and with a stem base that is at least ¼ inch thick, can be transplanted as early as feasible. They are not cold hardy, especially as seedlings. Tomatoes are typically planted well-below their bases as they grow advantageous roots along the lower stem. Physalis plants do not grow these roots from the stem.  Past recommendations suggested the plants could be planted deep, however this may lead to crown rot. Make sure the base of the plants are not below the soil.  They will probably need some initial support (Figure 1).

After planting, watch for pest insects daily. More information about pests and diseases can be found in the pest and disease tab.

Within a week after planting the 1st of several fertilizations should be applied. Rates of between 150 and 200 lb nitrogen per acre have been suggested for tomatillo, a related species. Plants should get at least 100 lb of nitrogen per acre (in row). If 50 lb nitrogen has been applied before planting, add at least another 50 lb per acre in split applications throughout the growing season. Potassium deficiency (yellowing and necrosis of leaf tips) has typically developed in late July, so make sure your soil potassium is at high optimum at pre-plant. 

Some selective pruning at nodes where branches are growing upward can prevent plants from sprawling and train them to have more upright growth.

Flowering will begin to occur even as 4-week seedlings. The plants are indeterminate and will grow and flower throughout the growing season.  Flowers are pollinated by bumblebees and ants (Figure 3). Care must be taken with the use of pesticides to protect pollinators (See pest management tab).

The first harvests should occur within two-and-a-half months after planting. Fruit falls from the plants when ripe (Figure 4.). A catchment system for the fruit can be built for easy harvest or plastic can be laid on the ground to keep fruit clean.

There are no peer-review published nutrient recommendations for goldenberries, however recommendations by Montes Hernández and Aguirre Rivera (1994) for a similar plant, the tomatillo, suggests a range of 107 to 214 lb N/acre. This should be performed in 3 or 4 split applications between planting in April and middle of August for high tunnel production.

High tunnels were prepared in April 2016 by amending soil with Smartleaf® compost at 4 lb (wet) per square ft, in row (7.9cuft/100 sqft). Three rows (80 sqft per row) were prepared. The compost was 0.5% nitrogen (N) and 0.04% phosphorus (P). A total of 1.6 lb of N and 0.1 lb P (organic, not all available) was applied per row. December 2016 soil tests showed adequate nutrients with an expected nitrogen release (ENR) of 150 lb. No further additions of compost were applied for 2017.

Seed for fruit were purchased from an online vendor. Seeds were germinated in early February and grown in plug trays until they were 5 to 8 inches high.  A soils test in September showed adequate nutrients except potassium.  Plants were planted in late March, and assigned positions by variety in each row.  A starter 20-20-20 fertilizer was applied as a soil drench.   Summer fertilizer additions included two 70% potassium nitrate and 30% urea in split applications totaling 34 lb N/acre each.

2016 Harvest

P. grisea fruit were harvested seven times between July 29th and November 10th. Fruit fall from plant when ripe.  Approximately 43 lb were collected from 15 plants. This averages about 46 oz per plant over the season.  Potential profit per plant is over $40 for this part of the season (30.5 oz x $1.33 per oz). Flavor quality of fruit decreased into the fall when sunlight levels decreased, however the plants remained alive 3 weeks after the first hard frost. 

2017 Harvest

P. grisea fruit were harvested seven times between June 24th and August 15th. Approximately 43 lb were collected from 15 plants. This averages about 46 oz per plant over the season.  Potential profit per plant is over $61 for this part of the season (46 oz x $1.33 per oz).

2020 Harvest

Nitrogen trials showed that plants should receive at least 100 lb N per acre (in row) for optimal yield. Keep soil-potassium levels at optimal to high.

Pests

Two-month seedlings, were predated upon by Three-lined Lema beetle (Lema trilineata) (Figure 1).

This was a major pest throughout the summer. In 2016, hornworm became a major problem by mid-August, through the fall was so in 2017 (Figure 2). The Lema beetle provides an interesting management problem because it needs to be controlled during flowering, preventing use of carbaryl (SevinTM )   or other effective beetle insecticides. P. peruviana was greatly effected by this insect pest. However, P. grisea was resistant to Lema Beetle due to growth rate, but may still be a management problem when plant is young.

Spinosad products (like EntrustTM), labeled for ground cherries, are effective for caterpillars and Lema Beetle but must be applied in the evening when pollinators are inactive. 

Other lepidopteran species were found. Early during development, many P. peruviana husks were found to have holes and fruit eaten inside by an unidentified moth (Figure 3). This was a common occurrence in both 2016 and 2017.

Disease

By August 2017, wide spread infection of Pythium and Fusarium caused major collapse of more than half of the plants in the high-tunnel ending the study. This occurred in successive years.