Heirloom New Zealand Spinach Planting Guide: From Seed to Harvest

If you’re looking to add a unique, heat-tolerant green to your garden, heirloom New Zealand spinach (Tetragonia tetragonioides) is a fantastic choice. Though not technically a spinach, this hardy plant is an excellent substitute during warmer months when traditional spinach struggles to thrive. With its thick, triangular leaves and slightly crunchy texture, New Zealand spinach is perfect for fresh salads, stir-fries, and soups. This Heirloom New Zealand Spinach Planting guide will walk you through everything from selecting seeds to harvesting, ensuring a productive crop of this remarkable heirloom green.

Quick Start Heirloom New Zealand Spinach Planting Guide – Complete Planting Guide Below

Heirloom / Open Pollinated New Zealand Spinach is a heat loving, short-lived, frost intolerant, perennial. We recommend soaking the Heirloom / Open Pollinated New Zealand Spinach Seeds for 24 hrs before planting, then direct sow seeds in full sun, covering with ½” of soil. Germination usually occurs in 7-10 days, but can be difficult. New Zealand Spinach plants like to sprawl, so you may want to trellis them to conserve garden space. Thin New Zealand Plants to 12-20″ apart.

The Complete Planting Guide for Heirloom New Zealand Spinach: From Seed to Harvest

What is Heirloom New Zealand Spinach?

Unlike true spinach, heirloom New Zealand spinach (Tetragonia tetragonioides) is part of the Aizoaceae family and originates from New Zealand, Australia, and parts of Asia. It’s a warm-season, tender perennial typically grown as an annual in temperate climates. Its sprawling growth habit and high heat tolerance make it ideal for summer gardens when other greens wilt.

The term “heirloom” refers to varieties that are open-pollinated and preserved across generations due to their unique flavors, colors, or growth traits. Heirloom New Zealand spinach is celebrated for its robust growth, rich nutritional profile, and adaptability, containing high levels of vitamins A and C, calcium, and iron.

How to Grow Heirloom New Zealand Spinach

To grow your own heirloom New Zealand spinach, start with high-quality seeds from a reliable supplier. New Zealand spinach seeds have a longer germination time, so a bit of patience and preparation will yield the best results. Follow these steps to successfully plant and cultivate your crop:

Step 1: Seed Preparation

1. When to Plant: Since New Zealand spinach thrives in warm conditions, it’s best planted in spring after the last frost has passed or in early summer in cooler climates. Ensure outdoor soil temperatures are consistently above 70°F (21°C) for optimal growth.
2. Soaking the Seeds: New Zealand spinach seeds have a tough outer coating, which can slow germination. Soaking the seeds in warm water for 24 hours before planting will soften the coating and improve germination rates.
3. Starting Indoors (Optional): If you’d like to get a head start, begin seeds indoors 3–4 weeks before the last frost. Plant the seeds in small, biodegradable pots for easy transplanting into your garden once outdoor temperatures are suitable.

Step 2: Planting Heirloom New Zealand Spinach

1. Selecting the Planting Site: Choose a sunny location where the plants can receive 6–8 hours of direct sunlight daily. Although New Zealand spinach can tolerate some shade, full sun will maximize its growth potential.
2. Soil Preparation: New Zealand spinach prefers well-draining, moderately fertile soil with a pH between 6.0 and 7.5. Before planting, enrich the soil with compost to improve its fertility and texture.
3. Direct Sowing in the Garden: Once outdoor temperatures are consistently warm, sow the seeds directly in the prepared soil. Plant seeds about ½ inch deep and space them 12–18 inches apart to allow for the plant’s spreading growth habit.
4. Spacing and Row Arrangement: New Zealand spinach is a vigorous spreader, so leave around 2–3 feet between rows to give each plant enough room to thrive and allow for air circulation to reduce the risk of disease.

Step 3: Watering and Care

1. Watering Needs: Although New Zealand spinach is relatively drought-tolerant, consistent moisture will ensure optimal growth. Water the plants regularly, keeping the soil evenly moist but not waterlogged. Watering at the plant base helps prevent fungal issues.
2. Mulching: Applying a layer of mulch around the base of your plants helps retain soil moisture, suppresses weed growth, and maintains a stable soil temperature—ideal for young seedlings.
3. Fertilization: Initial soil preparation with compost should be sufficient, but if growth seems sluggish, a balanced, organic fertilizer every 4–6 weeks will support development. Avoid excessive nitrogen, which can lead to lush but weak growth.
4. Pest and Disease Control: New Zealand spinach is resistant to many common pests, but it may occasionally attract aphids, spider mites, or leaf miners. Regularly inspect plants, and if needed, use an organic insecticidal soap to manage pest infestations.

Step 4: Harvesting Your Heirloom New Zealand Spinach

1. Timing Your Harvest: New Zealand spinach is usually ready for harvest about 55–65 days after planting. You can begin harvesting leaves once they reach 4–6 inches in length.
2. Harvesting Method: For the best flavor, harvest leaves in the early morning. Use garden shears or pinch leaves off by hand, taking only a few from each plant to allow continuous production.
3. Encouraging New Growth: Regular harvesting encourages the plant to produce more leaves. New Zealand spinach is a “cut and come again” plant, meaning it will continue to grow and produce throughout the season if you leave the main stems intact.

Step 5: Ongoing Maintenance and Successive Planting

1. Extended Care: New Zealand spinach will continue growing through late summer and into early fall, depending on the climate. Continue regular watering, weeding, and pest monitoring as needed.
2. Companion Planting: Pairing New Zealand spinach with crops like beans, peas, and carrots can improve its growing environment. These companion plants can shade the soil, retain moisture, and keep New Zealand spinach happy and healthy.
3. Successive Planting for Continuous Harvest: For a steady supply of fresh greens, consider planting new seeds every 3–4 weeks. This is particularly useful in climates where New Zealand spinach will continue producing until fall, providing a continuous harvest.

Benefits of Growing Heirloom New Zealand Spinach

1. Heat Tolerance: Unlike traditional spinach, which often bolts in warm weather, New Zealand spinach thrives in the heat, making it an ideal choice for summer gardens.
2. Nutritional Value: Heirloom New Zealand spinach is packed with vitamins A and C, calcium, and iron, offering a nutritious addition to your diet. Its mild, slightly salty flavor works well in both raw and cooked dishes.
3. Natural Pest and Disease Resistance: Thanks to its unique genetics, New Zealand spinach is naturally resistant to many common garden pests and diseases, requiring minimal intervention.
4. Versatile Use in the Kitchen: The mildly salty flavor of New Zealand spinach pairs beautifully with a variety of recipes, from fresh salads to stir-fries, soups, and sautés. Its thick, crunchy leaves also hold up well when cooked.

Managing Pests and Diseases in Heirloom New Zealand Spinach

While heirloom New Zealand spinach is generally hardy and resistant to many common garden issues, it can occasionally face problems with pests and diseases. Here are some effective methods for identifying, preventing, and managing these potential issues to keep your plants healthy and thriving.

Common Pests

1. Aphids

• Identification: These tiny green, black, or gray insects often cluster on the undersides of leaves and stems, feeding on plant sap. Their feeding can lead to curled, yellowing leaves.
• Management: Spray plants with a strong stream of water to dislodge aphids. You can also use insecticidal soap or neem oil, applying in the early morning or late evening to avoid leaf burn. Ladybugs, which are natural aphid predators, can also help control aphid populations.

1. Spider Mites

• Identification: Spider mites are tiny and can be hard to see with the naked eye, but you may notice fine webbing on the leaves or small yellow or brown spots as the mites suck sap from the plant.
• Management: Rinse plants with water regularly, as spider mites thrive in dry, dusty conditions. In case of a severe infestation, apply insecticidal soap or neem oil. Keeping the plants well-watered and humid can also discourage spider mites.

1. Leaf Miners

• Identification: Leaf miners tunnel through the leaves, creating winding, white trails that appear as they feed inside the leaf tissue.
• Management: Remove and dispose of affected leaves to prevent the larvae from developing into adults. Row covers can help keep adult leaf miners from laying eggs on your plants, and neem oil can reduce larval development within the leaves.

1. Caterpillars and Slugs

• Identification: Caterpillars and slugs can chew large holes in the leaves, sometimes consuming entire sections of the plant.
• Management: Hand-pick caterpillars and slugs from your plants, especially in the early morning or late evening. You can also place organic slug bait around the base of the plants or use copper tape to deter slugs. For caterpillars, using row covers can help prevent adult moths from laying eggs on the leaves.

Disease Prevention and Management

1. Powdery Mildew

• Identification: Powdery mildew appears as a white, powdery coating on the leaves, usually in warm, dry weather. While it doesn’t usually kill the plant, it can weaken it and reduce productivity.
• Management: Increase air circulation around the plants by providing ample spacing and keeping weeds under control. Water the base of the plant rather than the leaves, as excess moisture on leaves can encourage mildew. If powdery mildew develops, remove and discard affected leaves. Applying a diluted solution of milk and water (1 part milk to 9 parts water) can help prevent its spread.

1. Damping-Off Disease

• Identification: Damping-off primarily affects seedlings, causing them to wilt, collapse, and die at the soil line. It’s usually caused by fungi in overly damp conditions.
• Management: To prevent damping-off, start with sterilized soil and avoid overwatering young seedlings. Make sure containers have good drainage if starting seeds indoors. If damping-off occurs, remove and discard affected seedlings, and allow the remaining soil to dry before replanting.

1. Root Rot

• Identification: Root rot is often caused by waterlogged soil and poor drainage, leading to stunted growth, yellowing leaves, and wilting.
• Management: Ensure proper soil drainage and avoid overwatering. Adding compost to the soil improves its structure, helping it drain better and promoting healthy root growth. If a plant shows signs of root rot, reduce watering and consider transplanting it to a drier area with better-draining soil.

1. Downy Mildew

• Identification: This disease causes yellow or brown spots on the upper side of leaves, with a gray or purple fuzz underneath. It typically occurs in cool, wet weather.
• Management: Ensure good air circulation around plants and avoid overhead watering to keep the leaves dry. Remove affected leaves to prevent further spread, and consider using an organic fungicide if the disease persists.

Preventative Measures

• Crop Rotation: Rotate your crops each season to reduce the buildup of soil-borne pathogens that can affect New Zealand spinach. Avoid planting in the same spot where other susceptible plants, like traditional spinach or beets, were grown previously.
• Proper Spacing: Allow adequate spacing between plants to improve airflow, reducing the likelihood of fungal and bacterial diseases.
• Watering Techniques: Water at the base of the plants, as wet leaves can create conditions that encourage mildew and other diseases. Watering early in the day also allows leaves to dry by evening.
• Soil Health: Healthy soil can strengthen plants and make them more resistant to diseases and pests. Incorporate compost and organic matter to improve soil structure and drainage, and consider adding beneficial microbes to promote plant health.

By taking these preventative steps and monitoring plants regularly, you can reduce the risk of pest and disease issues and keep your heirloom New Zealand spinach plants thriving all season long. Healthy, well-maintained plants are not only more productive but also more resilient against potential garden challenges, ensuring a bountiful harvest.

Storing and Preserving Heirloom New Zealand Spinach

Once you’ve harvested your heirloom New Zealand spinach, proper storage and preservation techniques will help you enjoy its fresh flavor and nutrients well beyond the growing season. Here are some effective methods for storing and preserving New Zealand spinach:

1. Storing Fresh New Zealand Spinach

For short-term storage, fresh New Zealand spinach can last up to a week in the refrigerator if stored properly.

• Refrigeration: Rinse the leaves thoroughly to remove any dirt or pests, then pat them dry with a paper towel. Place the spinach in a plastic bag or an airtight container, lined with a paper towel to absorb moisture. Store in the crisper drawer of your refrigerator for maximum freshness.
• Moisture Control: Excess moisture can lead to quicker spoilage, so check the paper towel every few days and replace it if it becomes damp.

2. Freezing New Zealand Spinach

Freezing is an excellent way to preserve New Zealand spinach for long-term use, retaining much of its flavor and nutrients.

• Blanching: Begin by blanching the leaves to stop enzymatic activity, which helps preserve color, texture, and nutrients. Bring a pot of water to a boil, and add the cleaned spinach leaves. Blanch for 1–2 minutes, then transfer immediately to an ice water bath to stop the cooking process.
• Draining and Drying: After the spinach has cooled in the ice bath, drain it well and pat dry with a clean towel or paper towel to remove excess water.
• Packing for Freezing: Portion the spinach into freezer-safe bags or containers, removing as much air as possible before sealing. Label the bags with the date, and store them in the freezer for up to 10–12 months. Frozen New Zealand spinach works well in soups, stews, and sautés.

3. Dehydrating New Zealand Spinach

Dehydrating is another effective method to preserve New Zealand spinach, as it requires minimal storage space and keeps for a long time.

• Preparing for Dehydration: Wash and pat dry the leaves. Spread them in a single layer on dehydrator trays, or use your oven if it has a low-temperature setting.
• Dehydrating Process: Set the dehydrator to 125°F (52°C) and dry for 8–12 hours, or until the leaves are completely brittle. If using an oven, set it to the lowest temperature, leaving the door slightly ajar to allow moisture to escape.
• Storage: Once dried, crumble the leaves or store them whole in an airtight container in a cool, dark place. Dried New Zealand spinach can be used in soups, stews, and smoothies or rehydrated as needed.

4. Preserving by Pickling

For a unique flavor, consider pickling New Zealand spinach stems. Pickling is an easy preservation method that also adds a tangy taste to the spinach.

• Preparing the Spinach Stems: Trim the stems and wash them well. Blanch them briefly in boiling water for 1 minute, then transfer to an ice bath to stop the cooking.
• Making the Pickling Brine: In a pot, combine equal parts vinegar and water, along with a tablespoon of salt and optional spices like garlic, dill, or mustard seeds. Bring the mixture to a boil.
• Pickling Process: Pack the blanched spinach stems into sterilized jars and pour the hot brine over them, leaving a small amount of headspace. Seal the jars tightly and store them in the refrigerator. Pickled New Zealand spinach stems can be enjoyed within a few weeks and will keep in the fridge for up to two months.

5. Using Vacuum Sealing for Extended Storage

If you have a vacuum sealer, you can use it to extend the storage life of both fresh and blanched New Zealand spinach.

• Vacuum Sealing Fresh Spinach: For shorter-term storage, vacuum seal fresh, dry spinach leaves and store them in the refrigerator. This method can keep the spinach fresh for up to two weeks.
• Vacuum Sealing Blanched Spinach for Freezing: Blanch the spinach, dry it well, then vacuum seal it before freezing. This reduces freezer burn and keeps the spinach fresh for up to a year.

By using these storage and preservation methods, you can enjoy the delicious taste and health benefits of heirloom New Zealand spinach year-round, adding variety and nutrition to your meals long after the growing season has ended.

Saving Seeds from Heirloom New Zealand Spinach

Saving seeds from your heirloom New Zealand spinach plants is a fantastic way to preserve your crop for future seasons. Seed saving ensures that you’ll have a steady supply of this heat-tolerant green and helps maintain the plant’s unique genetic traits. Here’s how to successfully save seeds from New Zealand spinach:

Step 1: Selecting Plants for Seed Saving

To start, choose a few of your healthiest, most vigorous plants to leave for seed production. Look for plants with strong growth, disease resistance, and abundant leaf production. Selecting the best plants ensures that the next generation of seeds will inherit these favorable traits.

Step 2: Allowing Plants to Flower and Produce Seeds

Unlike other spinach varieties, New Zealand spinach will flower and go to seed when exposed to the right environmental conditions. As temperatures cool at the end of the growing season, allow your chosen seed plants to grow without harvesting any more leaves. Soon, the plants will begin to produce small, inconspicuous yellow flowers. Once pollinated, these flowers will develop into seeds.

Step 3: Collecting the Seeds

After flowering, New Zealand spinach will produce small, round seed pods along its stems. Let the seeds mature fully on the plant; they’ll turn brown or black when ready for harvesting. This may take a few weeks, depending on the weather. When the seed pods are dry and brittle to the touch, it’s time to collect them.

Gently cut the seed-bearing stems with a pair of garden shears, being careful not to shake off the seeds. Place the cut stems in a paper bag or container to catch any loose seeds that might fall.

Step 4: Cleaning and Drying the Seeds

After collecting, separate the seeds from any remaining plant material. Rub the seed pods gently to release the seeds, then remove any leftover debris. Once cleaned, lay the seeds out on a dry surface, such as a paper towel or a screen, and allow them to air-dry in a warm, dry area for a few days to ensure they are thoroughly dried.

Step 5: Storing the Seeds

Once your seeds are dry, store them in a cool, dark, and dry place. Use airtight containers such as glass jars, seed packets, or small envelopes to protect the seeds from moisture. Label each container with the date and type of seeds to keep your collection organized. Stored properly, New Zealand spinach seeds can remain viable for up to 3–5 years.

Tips for Successful Seed Saving

• Avoid Cross-Pollination: If you are growing multiple spinach varieties, be aware that cross-pollination may affect seed purity. To keep your heirloom New Zealand spinach seeds true to type, grow it away from other varieties that may cross-pollinate.
• Rotate Seed Crops: Each year, rotate which plants you save seeds from to maintain genetic diversity and vigor within your New Zealand spinach crop.
• Label and Organize: Good labeling and organization are key to successful seed saving. Clearly mark seed packets or containers with details such as the harvest date to track seed freshness.

By saving seeds from heirloom New Zealand spinach, you can enjoy a sustainable, self-sufficient gardening practice that keeps your garden thriving season after season. Not only does this help preserve the unique qualities of the plant, but it also allows you to share seeds with other gardeners interested in growing this unique, heat-loving green.

Conclusion

Adding heirloom New Zealand spinach to your garden is a great way to diversify your summer greens. Its resilience in hot weather and low-maintenance nature make it an excellent choice for gardeners looking to grow healthy, flavorful greens in the summer months. By following this guide on how to grow heirloom New Zealand spinach, you’ll be well on your way to a successful harvest, enjoying nutritious greens long after traditional spinach has faded.

FAQ: Heirloom New Zealand Spinach Planting Guide