Pawpaw Care Guide
The Pawpaw (Asimina triloba) is a remarkable fruit tree native to the temperate regions of North America. Known for its unique, custard-like fruit, it’s a hardy tree that thrives in the right conditions, offering not only a delicious fruit but also an attractive small tree for your garden. Here's everything you need to know to grow and care for pawpaw trees successfully.
1. Climate and Hardiness
- Hardiness Zones: Pawpaw trees are hardy to Zone 5, meaning they can withstand winter temperatures as low as -15°F.
- Preferred Climate: They thrive in temperate, humid climates with warm to hot summers and mild to cold winters. A minimum of 32 inches of rainfall annually is ideal, with most of the rain falling in spring and summer.
- Geographic Range: Native from the Gulf Coastal Plain to southern Michigan, pawpaw grow best in areas with high humidity and adequate rainfall.
- Cold Tolerance: In colder regions (like Zone 4, e.g., Northfield, MN), pawpaw trees can still be successful, but the trees will benefit from a strong specimen to start with, planted in a location out of the wind.
2. Site Selection, Soils & Habitat
- Exposure: Pawpaw trees prefer full sun but will tolerate partial shade. In shaded areas, however, they may grow with a more spindly open branching habit and fewer lower limbs, producing less fruit.
- Wind Protection: Due to their large leaves, pawpaw trees benefit from wind protection. Strong winds can damage the tree or its leaves.
- Soil Preferences: Pawpaw prefer slightly acidic soil with a pH of 5.5-7. The soil should be deep, fertile, and well-drained. Although pawpaw can tolerate a variety of soils, they will not thrive in poorly drained or very alkaline soils.
- Tree Size: Pawpaw are small trees, typically growing to a height of 15-25 feet. In shaded areas, they may grow more vertically with fewer branches.
3. Pollination: Natural & Artificial
- Self-Incompatibility: Pawpaw trees are generally self-incompatible, meaning they cannot pollinate themselves. You’ll need at least two genetically different (different variety) trees for fruit to set.
- Flowering: The flowers are protogynous, meaning the female stigma ripens before the male pollen is shed, making natural pollination difficult. Natural pollinators, like flies and beetles, will produce satisfactory results, especially as the tree matures. Because pawpaw pollination can be a bit tougher in nature, some growers will hand pollinate to increase their chances of fruit yield. While not necessary when growing pawpaw, it can be a fun activity to experiment with.
- Hand Pollination:
- Use a small, flexible artist’s brush to transfer pollen from one tree’s flower to another.
- The pollen is ready when the anther ball is brown and loose, and the stigma is glossy and green.
- Careful not to overburden the tree with fruit as this can cause smaller fruit and breakage due to weight.
4. Watering and Irrigation
- Regular Watering: Pawpaw trees are moderate water users. Keep the soil consistently moist but not soggy. During dry spells, ensure that the tree receives enough water to prevent stress.
- Drought Tolerance: Once established, pawpaw trees can tolerate some drought, but they will produce the best fruit when provided with regular watering during the growing season.
5. Fertilizing
- Fertilizer Needs: Pawpaw trees don’t require a lot of fertilization, but they will benefit from a balanced fertilizer in the spring if needed. Avoid high nitrogen fertilizers, as this can lead to excessive vegetative growth at the expense of fruit production.
- Compost and Mulch: Organic matter (like leaf mold compost) can be added as a top dressing to provide nutrients and help retain moisture. Pawpaw’s ideal soil components are a forest floor environment, if you’re planting in a field, it could be helpful to incorporate some topsoil from a wooded area.
6. Pruning
- Pruning for Shape: Prune in late winter or early spring to shape the tree and remove dead or damaged branches. A central leader structure (single trunk) is often preferred for ease of harvesting. When pruning, observe the buds on the branches–larger buds will typically be flower/fruit buds, so you’ll want to leave those going into the growing season.
- Removing Suckers: Pawpaw can send up root suckers, which should be removed if they are not wanted to prevent spreading. These are especially common in older trees.
7. Pests and Diseases
- Pests:
- The Zebra Swallowtail Butterfly (Eurytides marcellus) larvae feed on pawpaw leaves. However, they are not usually in large enough numbers to cause significant damage. In fact, their presence is often seen as a positive sign.
- Deer generally avoid pawpaw trees, and the tree’s leaves, twigs, and fruit are not attractive to them. Protecting young trees with a cage is still wise, as a particularly adventurous deer could cause significant damage.
- Diseases: Pawpaw are relatively resistant to most common tree diseases. However, they can be susceptible to fungal infections if growing in overly wet conditions. Make sure the soil is well-drained to prevent root rot and fungal issues.
8. Fruit Quality and Harvesting
- Ripeness:
- Ripe pawpaw are ready to eat when the fruit has slightly softened and is about to fall from the tree. The skin will turn to a lighter, more yellow-green color.
- Overripe pawpaw (with skin turning brown) are still edible but are not as flavorful.
- Cultivars like Allegheny and Rappahannock ripen early, while Shenandoah and Wabash are late-season cultivars.
- Fruit Quality: Pawpaw fruit is custard-like in texture, with a sweet, fragrant flavor resembling banana, mango, and custard. The fruit weighs between 5 ounces to 1 pound and should be plump, round, and free of blemishes.
- The flesh should be smooth and melting, with a complex and lingering sweetness.
- The fruit contains large, dark seeds, which are easily removed by scooping out the flesh with a spoon.
9. Uses of Pawpaw
- Fresh Eating: The most common way to enjoy pawpaw is by simply eating it fresh. Slice the fruit in half, scoop out the flesh, and spit out the seeds.
- Cooking: Pawpaw fruit is best suited to recipes requiring no or minimal heat to preserve its delicate flavor. It works well in:
- Ice cream, sorbet, and chiffon pie
- Mousse, banana bread, or smoothies.
- Mint and pawpaw also pair well together in desserts.
- Storage: Pawpaw fruit does not store well for long periods, but it can be frozen for later use in recipes.
10. Conclusion
Pawpaw trees are a delightful addition to any garden, offering both ornamental beauty and delicious fruit. With some care in site selection, pollination, and basic maintenance, you can enjoy the unique custard-like fruit that compares favorably to some of the world’s best tropical fruits like mangoes and pears. Their resilience and low maintenance make them an excellent choice for gardeners who are interested in growing something a little out of the ordinary!
Happy planting and enjoy the sweet rewards of your pawpaw tree!