Establishing pawpaws aka Michigan bananas. Year one.

pawpaw Taylor

pawpaw sunflower

I like to grow unusual plants, preferably native to our area. It sounds paradoxically, but some native plants are still unusual in US gardens, for example paw paw and  Aronia.  This year I planted two grafted pawpaw trees: Sunflower and Taylor.

Pawpaw (Asimina Triloba) is native to the Eastern US, but not many people know about this hardy (up to USDA zone 5 and some varieties up to zone 4) distant relative of pineapples. The trees grow naturally in the US Eastern forests under the canopy of bigger trees therefore, they tolerate partial shade. However, pawpaw trees produce better in the full sun and have to have a different genetic variety for cross pollination. People wonder why they have never seen pawpaw fruits in the forest, this is because the trees are usually growing as an expanded clone patch and therefore do not fruit. Pawpaw fruits shelf life is short and this is why it is not seen in supermarkets either.

The trees have large tropical looking leaves, and can grow up to 25 feet tall. Pawpaw trees  bear large green fruits, the largest fruit native to North America. I have not tasted the fruit myself, but according to the plant nursery where I bought the trees from, it tastes like vanilla custard and it is rich in protein and antioxidants. This sounds very attractive. The fruits can be eaten fresh or made into cakes like banana bread. The flowers of pawpaws are not their most attractive feature, they are small, look downwards and smell bad. The flowers evolved for being pollinated by flies, not by bees. I hope the bad smell does not carry. It is suggested to hand pollinate pawpaws to insure the maximum amount of zygotes.

The small grafted trees arrived from the nursery potted. The instruction said that they should not be exposed to full sun for the first 2 years of their lives, but for good fruit production they should be in full sun. Also, because of long and fragile tap root pawpaws should not be transplanted. Armed with this information I had the tricky task of creating a growing site in a permanent location, in full sun but somehow shaded.

Planting

1. I chose the sunny bank of our fish pond so the long tap root would eventually have access to water. Pawpaws like slightly wet soils, but not waterlogged..

2. I dug the planting hole 2 feet deep and 2 feet wide and filled it with Miracle Gro Garden Soil for Trees and Shrubs mixed with peat moss in a proportion of 3 to 1. Pawpaws like rich slightly acidic soils.

3. I planted the plants with the soil at the same level as it was in the pot and mulched 2 inches and watered. I watered the plants regularly throughout the summer and kept the planting site moist, but not waterlogged.

Now comes the tricky part: creating the shade in full sun.

The young trees that I received from the nursery were only 2 feet high, so I put a peony hoop around each of them and covered the hoop with burlap fabric. I only covered the top and the sides that were exposed to sun the most. It worked, both trees opened their leaves and started to expand the branches. As the trees grew I would come up with a bigger structure on which to spread the burlap.

The other challenge is late frost.  The spring weather at the end of April is usually rainy and very warm in our area. However, sometimes in May or even at the beginning of June we have a heavy frost. Because the trees were grafted and suitable for zone 4 I just covered them with plastic to protect against the frost. It did not work, one of the trees lost all of its leaves. Fortunately, it recovered and grew new leaves again. The next time frost came I covered the trees the same way I did grapes, with two layers of fabric (old linens) and plastic. It worked. Conclusion: young pawpaws are sensitive to late frost just like grapes, and need protection.

As it often happens, the plant nurseries claim that pawpaws are not bothered by pests or diseases. The pest part turned out to be true. I found only a few holes that appeared to have been made by slugs. Deer did not browse on the trees either.  As regards to diseases, it was not quite true. In our rainy hot spring the trees were affected by some fungus. The edges of the leaves were blackening and then the leaves would drop off. First I used Copper fungicide and it did not work. Then  I sprayed the trees a few times (each time after rain) with  Chlorothalonil such as in OrthoMax Garden Disease Control. I used the dose for the stone fruits since pawpaw was not sited in the instruction. It worked marvelously. The disease stopped and did not come back for the rest of the season.

Both trees grew large leaves and put out a few branches, but did not increase in height. That was expected because pawpaws grow slowly. We have almost tropical summers (very hot and incredibly humid) in our area, but winters are of the USDA zone 4. Very strange climate, but I hope my two pawpaws will survive to the next growing season.