Some of the tastiest and most interesting fruits and vegetables are more akin to warmer climates then what we have here in Ireland and growing such plants has not been an option and can’t be done on a large scale. It is however possible to grow a small amount of exotic plants and seeds in your home or greenhouse using a propagation kit and heated greenhouse.
Starting seeds can be a bit hit and miss with some species of plants proving to be quite difficult to grow. Plants such as morning glory, banana, citrus, grape and cannas all prefer warmer, damp conditions to germinate and grow. To achieve these conditions there are a number of things you can do. First it is recommended to invest in a high dome propagation kit; these handy kits come with a plastic cover which traps heat and increases soil and air temperatures by approx 4 or 5 degrees celcius.
Another way to increase the success rate and germination rate of your exotic seedlings insure that you provide the best soil mix. Prepare you propagation Kit by added a mix of well drained compost and cover over the soil is a fine mulch such as perlite or horticulture grit. The soil mix that you use can vary for different exotic seedlings as some prefer more damp conditions but a general ratio would be 1 part perlite to 2 parts compost.
Position of your propagator is also important; choose a warm and sunny location such as a bright windowsill, conservatory or greenhouse. Choose a spot that receives the most sunlight but to wary of temperature fluctuations at night time. Seedlings and especially exotics do not like sharp changes in temperature that can occur at a window sill. The propagator will minimise this but it would be recommended that you move your seedlings away from the windowsill on cold nights. Remember exotic seedling require approximately 23 degree Celsius to grow.
It is also important to minimise the amount of disturbance to your young seedlings as possible. This means that to soil and roots should not be touched and that when potting on or transplanting from the propagation kit care should be taken to reduce stress on the plants. Using biodegradable pots such as coir pots is ideal as these pots can be planted directly into the ground without any root disturbance.
You will often find that exotic seeds require having their seed coat scratched or nicked prior to sowing to induce germination. This can be done by rubbing the seed against sandpaper or cutting the hard seed coat with a knife. Other exotic seeds benefit from being soaked in water for 24 hours prior to sowing in a propagation kit.
Lastly, the sprouted seedlings will require high humidity to reduce water loss. To increase humidity in a propagator you can close the vents, preventing fresh air from getting in. To increase the humidity in a greenhouse you can pour water on the floor in warm weather, the water will evaporate increasing water vapour or humidity in the air.