Plant your tulip bulbs in late October, November or December. The cold temperatures help to wipe out viral and fungal diseases that lurk in the soil and which may infect the bulbs. Planting late is a traditional means of disease protection.
Most gardening books recommend planting tulips at twice the depth of the bulb – at about 8cm (3in) in the case of most tulips – but I prefer planting tulip bulbs much deeper. If planted deeply, tulips are less likely to try to reproduce and are more likely to flower for year after year.
You can plant tulips in your borders individually or in small groups amongst existing perennials, but if you are planting a lot of bulbs, it may be easier to dig out a trench or hole about 20cm (8in) deep. If you garden on heavy soil, cover the base with 5cm (2in) of washed sharp sand, horticultural grit, or spent compost. You can also add a handful of bone meal to encourage formation of next year’s flowers and mix it into the soil/grit at the base of the hole or trench.
Place the tulip bulbs, pointy end up, about 8cm (3in) apart and cover with soil. Again, if you garden on heavy soil you can mix grit at approximately one-third grit and two-thirds infill soil.
If you’re short of space, cover the bulbs with soil and then add a second layer of bulbs before filling in the hole. There is still enough soil above the bulbs to allow you to overplant the tulips without damaging them.
To help you plant your tulips more easily, you can use a traditional bulb planter, or bulb planting trays. If you're planting through herbaceous plants and shrubs or through grass, a bulb planter is brilliant – it’s like a massive apple corer and when you press it into the ground it cuts out a core of soil. Plop a little bit of spent compost or grit into the bottom of the hole, add the tulip bulb and backfill with grit and compost just like you would in the trench.
