Prepared hyacinths have a fabulous fragrance and are perfect for bringing a Spring feeling indoors during the late winter months. Care should be taken with hyacinths as they can irritate the skin causing itching; it is advisable to wear gloves when handling them. Always unpack bulbs and plant on arrival. Plant with the tips of the bulbs just showing through the compost - use a loam-based potting compost like John Innes No.2. You can also use bulb fibre if there are no drainage holes in the container. We advise against using peat-based compost.
In order to allow the roots to develop, hyacinths need to be kept in a cool dark place with a temperature of no more than 7°C for around 8-12 weeks. You can place them in a black polythene bag, or put them in a dark cellar or cardboard box in a shed or garage. You can also put the hyacinth outdoors covering them with bark or compost but take care as worms/insects could get into the soil. Placing the pots in a cold frame on a solid base can help prevent this. You will need to check regularly to make sure the compost is not drying out, but it is important not to get any water on the shoots as this can cause the flower to rot. Don’t allow any water to penetrate the top of the bulbs either or they will rot the flower bud and the bulb inside.
When the shoots are around 2.5 to 5 cm high, gradually increase the light and temperature. If they are brought out into the light and warmth too soon they can produce elongated leaves and weak flowers. It is best not to place them near a radiator or draught. Hyacinths like a humid atmosphere, so you can sit the bowls inside a larger bowl or tray filled with a little gravel with a little shallow water. However, avoid waterlogging the compost, as damp conditions together with poor drainage can cause rot and fungal diseases. If the leaves start to grow faster than the flowers put them back in the dark for a few days to hold them back. Feed hyacinths every couple of weeks with high potash feed - liquid seaweed is ideal: it’s organic and comes from a sustainable source.
If you are planting the bulbs in glass vases, add water to the vase and then add the bulb, pointed side up. It is important the water does not touch the base of the hyacinth bulb as this will cause base rot. Similarly, don’t let water into the top of the bulbs as the flower bud and bulbs can rot. Place them in a cool dark place for a few weeks, as per the same tips above for potting in bowls.
When flowering is finished remove the flower stem and allow the leaves to die back naturally; they can then be planted out in the garden.
As well as wearing gloves when handling Hyacinth bulbs, it goes without saying that they should not be eaten as they contain compounds which can cause stomach discomfort, nausea and they can also affect blood pressure. The bulbs can also be poisonous to cats and dogs.
Poor results with flowering can occur if the bulbs do not get a sufficient period of cool temperatures, if they are brought out of the dark too soon or if the compost is too wet or dry. If water enter the top of the bulbs they will rot the flower bud and the bulb inside.