Pot vs In the Ground
It is crucial to keep small seedling in a pot for as long as possible until the stems showing sign of browning. Ideally for 2-4 years depending the type of plant you purchase. The longer they take time to establish in a pot is the better they cope when they need to be repotted or replanted in the ground. It might be that some plants would just happily growing in a pot for its life time as long as they have good quality soil, heat, suitable and regular fertiliser and established root system and to some extend a partial shade and protected from frost. If you lives somewhere Up North, you may be luckier and able to plant many type of subtropical plants directly in the ground when they are about 8-12 months old seedling, although a staking, wind break may still be required. We still recommend to wait until the root system is well established. Usually seedlings can be repotted into a larger size pot once their roots are outgrowing the smaller pot they are in. The ideal size of pot is three times the size of root ball. Be careful not to break or hurt the root system during transplanting.
Sunlight/Heat
Most of Subtropical plants loves plenty of heat and sun. It is crucial to keep your young seedling in full or partial shade during summer season. Keeping the plant warm between 21-29 degrees Celsius is ideal, or they are happy in a greenhouse or growing indoors at room temperature. Other time, keep your plant protected from frost. From our experience growing Subtropical plants over the years, they do love the heat but they do not like to be under the direct sun. We highly recommend to place the plant in a semi shaded area at the very least.
Watering
All Subtropical plants, doesn't like wet feet. Other than citrus, subtropical plants does not need much watering at all except for summer, where the watering routine can be increased. Around summer, the plant may need watering 1-2 times a day, or if they are in a greenhouse and planted in a pot. If they are in the ground, and received partial shades, once a day watering is ideal. Around winter, only water the plants once every 3-4 days. If your plant is in a pot, poke your second finger in the soil, only water when half the finger length is dry. If you are keeping your plant indoor, be weary of heat pump usage, especially during winter time, as may dry out the moisture in the air and this will hurt the plant. As a remedy, gives the plant, less watering but more misting or foliar spraying instead.
Soil
Subtropical plants loves a rich and well draining soil. If you have a good quality and organic potting mix, please ensure to add 30-50% mix of fine pumice or sand. If you are planting into the ground, ensure to add some sand to it or compost. For a healthier plant, add mulch around the base of plant, but be careful not to touch the stem.
To transplant, prepare a good quality potting mix in advance before repotting the plant. Try not to transplant any subtropical fruit trees directly into the ground until they pass their second winter at the minimum. It is a good idea to top up the soil with compost and the potting mix at least 2 times a year to ensure your plant receives all the nutrient it needed.
Fertilising
Plants will grow to the size of the pot, and minimal watering and fertilising is required around winter and more often around the spring till the end of summer. Subtropical plants usually prefer a well composted animal manure as fertiliser. However an alternate feed with general fertiliser is acceptable. During winter, cease any granular type of fertiliser, but offer liquid fertilising like the heavily diluted seaweed or worm juice every week 2-3 weeks. Around spring right to end of summer, offer the plants with weekly diluted liquid fertiliser, and monthly granular or general fertiliser. Foliar spraying will benefit the plant if you could alternate with the liquid fertiliser during growth season. Never used sheep pellets for pot plants - especially for subtropical fruit plants.
Pruning
Pruning should be done during the first year of growth to reduce the plant to one healthy shoot, and branches lower than 30 in (75 cm) should be removed. At the end of the year, the plant is topped. During the 2nd and 3rd years, the tree is carefully shaped. Thereafter, the tree should be pruned immediately after harvesting at the beginning of dormancy and 25 to 50% of the previous year's growth may be removed. Sometimes a second lighter pruning is performed just before flowering. There will be great improvement in size, quality and number of fruits the following season.
Important Notes
- Keep subtropical plants in the warmest area indoors or in a greenhouse/polytunnel for their first 1-2 years and slowly introduce to a shaded outdoor area when the weather is good.
- Keep young seedlings protected from frost and strong wind. Other than Cherimoya plants, do not attempt to replanted subtropical plants during winter.
- During summer time, it is important to have a lot of air circulation around the plant. If growing under polytunnel or greenhouse, you may need to let some air in, this will do plant good.
- All plants sold by Exotica NZ will be cleaned, weeded, fed and watered well before their journey to you. In most cases, we even send the plant with extra fertiliser to be used after 4-5 weeks or as a top up when you want to transplant it. It is crucial that you gives the time for your plant to acclimatized.
- Upon receiving your plants leave it as is for a week before you make any changes. All it needs from you is watering and keeping a close eye on any signs of stress and plant being lethargic from its journey to you such as wilted leaves, dropping or yellowing leaves. In normal event, the plant will bounce back after a few days. The plant may be restaking or firming the soil around the base or given a plant tonic before replanting.
Good luck and happy growing!
Disclaimer: This is generic advice only and your results may vary