Papaya: growing from seed & plant care

Even here in the UK, with the proper care, papaya seeds can be successfully planted and even eventually bear fruit. Papaya seeds can be eaten as well as sown to grow trees. Keep reading to discover more about this vibrant, versatile fruit tree.

The papaya (Carica papaya) is a tropical plant with remarkable properties. And it is entirely possible to grow your own papaya tree in the UK and if you follow our tips, you will be rewarded with its delicious fruits in no time. Read on to find out how to plant papaya trees at home and how to properly care for them year-round.

Papaya plant: origin and properties

It is said that the term papaya is derived from the Arawakan language of the Central American Arawak peoples, who referred to it as the “tree of health.” It belongs to the family Caricaceae and is native to Mexico. Nowadays, the papaya is cultivated in tropical and subtropical areas such as Australia, India, Central and South America, and Africa.

Papayas are semi-woody, evergreen trees. It can reach a height of 3 to 4 m in a pot, but it can grow much taller in its natural environment. The palm-like papaya trunk is hollow within or filled with spongy tissue, sparsely branched and not as woody as trees generally are. The papaya plant has an abundance of milky sap throughout, and a particularly shallow, widely spread root system.

The long-stalked, papaya leaves alternate to form a tree crown. The leaves growing further down the trunk, die back and leave behind leaf scars. The papaya leaves can easily grow to over half a metre long, with each deeply lobed leaf form resembling a spread hand.

Papaya flowers come in a pleasing variety of shapes and colours. Depending on the species, they can be white, yellow or cream-coloured. Carica papaya, the most common species, has small white star-shaped flowers that resemble propellers. Papaya flowers conveniently grow from the leaf scars of the dead leaves. Both papaya flowers and fruits can be found on one plant at the same time. Papayas are dioecious plants – this means that a plant bears either exclusively male or female flowers. As a result, successful fertilisation requires two papaya plants of opposite sexes. After 10 to 14 months, the first flowers emerge and soon thereafter, the tree bears its first fruits.

The oval papaya fruits have a yellow-green skin and weigh 500 g to 5 kg, depending on the species. Interestingly, since the difference between fruit and vegetable is sometimes vague, the papaya cannot be precisely classified as either! Unripe papaya is cooked like a vegetable, whereas the ripe papaya is eaten raw and is known for its sweet taste. At first, the fruit’s flesh is white, but it eventually turns yellowish-orange or red as it ripens. The fruit’s cavity is filled with an abundance of black seeds. They are around the size of peppercorns and are rarely eaten.

Tip: Find out how to eat a papaya here.

Even if the papaya fruits are harvested unripe, they can still continue to ripen due to their climacteric nature. This means that even after they are picked off the tree, their cellular respiration continues the ripening process.

Growing papaya from seeds

As papayas are originally from tropical climates, they can only thrive in the UK if they are first started indoors and then later placed in a pot in a conservatory or greenhouse or on a balcony or terrace in summer. To ensure germination, sow the papayas seeds in a grow pot and place in consistently warm spot, like a greenhouse or windowsill. The young papaya plant likes a bright, warm location, with a high humidity of 60% or more. From a height of about 15 cm, it requires a sunny spot. In warm summers, a wind-protected, sunny outdoor location is best – the papaya thrives in direct sunlight. Rain, wind gusts and cool weather, on the other hand, endanger the fruit. In winter, keep the papaya plant in a warm, sheltered place.

Our Plantura Organic Herb & Seedling Compost is an ideal growing medium for the young, delicate papaya plants. Our compost provides the ideal growing conditions for the papaya roots, which are rather small and sensitive.

Instructions: sowing papaya seeds

1. Prepare the papaya seeds: Cut a ripe papaya fruit in half and use a spoon to remove the seeds. Rinse the seeds with water and remove the remaining pulp. Then rub off the gelatinous layer around the seeds using kitchen towel, as it contains substances that inhibit germination. Once the seeds are dry, plant them promptly or store them in a cool place at a temperature below 15 °C.
2. Prepare the grow pots: Fill a few seed pots with growing medium. Sow one seed per pot and cover with 0.5 cm of soil. Then, moisten the soil using a spray bottle. Cover the pots with a transparent cover to create a highly humid atmosphere. Remember to regularly air the pots.
3. Germination period: Always keep the substrate moist, but not wet, and air the seeds daily. The ideal germination temperature is 25 – 30 °C. After approximately two weeks, the first, fine shoots will appear. In the early stages, the papaya seedling prefers a bright, but not overly sunny location. Use a spray bottle to moisten seedling regularly.
4. Repotting: As soon as the first leaves of the papaya plant are visible, it can be repotted into a pot with regular nutrient-rich potting compost. Choose a pot size that can accommodate the plant’s growth for at least a year. When repotting, be especially gentle with the young papaya plants, as the roots are very sensitive.

How to care for papaya trees

Proper care is essential for your papaya plant to thrive all year round in the conservatory or on the terrace.

Watering and fertilising

The papaya plant needs to be watered regularly to maintain soil moisture but be careful to avoid waterlogging. Water less in winter. Keep the humidity above 60% all year round.

It is not necessary to fertilise your papaya in the first two weeks following germination as the seedling receives enough energy from the seed’s endosperm. After that, feed the papaya once a fortnight. For the first two years, a half dose of fertiliser is sufficient. Our Plantura Liquid Flower Food is ideal for feeding papayas. The liquid fertiliser ensures a sufficient supply of nitrogen and is easy to apply using a watering can. Remember to maintain the papaya plant’s nitrogen levels, as insufficient nitrogen leads to decreased fruit production.

Tip: To achieve lower branching, the papaya tree can be pruned. However, pruning is not necessary, so keep in mind that it increases the risk of disease.

Repotting

Repotting papaya is also a key part of the annual programme. It is important to choose the right pot size so that the roots have enough space. When repotting, make sure to not damage the root ball and replant the papaya plant at the same height as before. Use a nutrient-rich, humus-rich, partly sandy and well-drained potting compost to prevent waterlogging. Mix our Plantura Organic Flower Compost with about 30% sand to make an ideal growing medium for your papaya plants. As our compost is peat-free, it provides a good balance of water drainage and water retention, which is very beneficial for papayas.

Diseases and pests

Papaya plants can be damaged by diseases like powdery mildew, a fungal disease that is easy to recognise with its white or grey patches of fluffy spores. An unpleasant infestation of spider mites (Tetranychidae) can also weaken the plant.

Is the papaya hardy?

No, the papaya is not hardy. Move the plant to a protected, warm winter location before outside temperatures plummet. The critical temperature is 11 °C, so the wintering place must be warmer than 11 °C. Bright lighting is also beneficial to successful overwintering. For example, your papaya can spend the winter happily in the conservatory or beneath a skylight. A less natural alternative to a conservatory, skylight, or south-facing window is a powerful plant lamp.

During this time, water your papaya less. If the papaya plant gets too cold, blossoms and fruits may fall off. But do not panic if the papaya loses its leaves; they will regrow in spring. After the winter, slowly acclimatise the papaya tree to warmer temperatures and outdoor conditions.

Can you harvest home-grown papayas?

Yes, but the first flowers only appear about 10 to 14 months after sowing. Flowering is dependent upon proper care, a sheltered location, abundance of light and warmth, sufficient fertiliser, and proper overwintering procedures. Once the first flowers have bloomed and been fertilised, you will not have to wait long to harvest your first juicy papaya fruits.

Can you eat papaya seeds? The flesh of the papaya is a versatile food, and even the black papaya seeds are edible. They taste slightly spicy and are even used as a pepper substitute in some countries.