Will daffodils and tulips survive next to each other ?
From my own gardening experience, and that of the International Flower Bulb Centre, Hillegom, Holland tulips and daffodils do well in the same flowerbed. Both are low maintenance plants. Include an organic fertilizer such as compost or well-rotted manure into the soil before planting in the late autumn and mulch the area with 2-3 cm (1 inch) of organic material: peat, leaf litter, or compost to provide further nutrients.
When flower bulbs and other plants increase their numbers entirely on their own, it is evidence that they are being provided with the habitat they enjoy.
It is true that cut daffodils must be separate from cut tulips and other blooming plants in a vase because the cut daffodils exude a substance which causes cut flowers to wilt. Frequently, flower arrangers put daffodils into a test tube-like vase within the bouquet ensuring that the two liquids don’t interact.
Fortunately, squirrels do not like daffodils, but to prevent them from disturbing tulips there are two methods to try. Just above the tulip bulbs under the soil, place a layer of chicken wire to deter digging. Or you may try commercially pelleted chicken manure sprinkled over the tops of the bulbs which deters the rodents while also providing nutrients.
Both bulbs are a joy in early Spring, and you can enjoy a longer display by choosing early, mid- and late bloomers. Good luck with your planting.