Heliotropes
Are more easily raised from seed than from cuttings, which require special care. Several of the new varieties, like Lemoine’s seedlings, give exceptionally large and early flowers, ranging in colour from pure white through all the shades of lavender, purple, and blue to deep indigo. If wanted for winter blooming the seed may be sown any time during the spring, but for bedding out it should be sown in February or March, and the plants duly potted off and plunged in a box of sand in a warm, sunny window, or a hotbed, until it is time to bed them out in the open ground. The compost should contain a large proportion of leaf-mould—three-fourths mould and one-fourth loam and sharp sand.
The seeds of Heliotrope must be kept merely moist, never wet and never allowed to dry out, or they will not sprout; keeping the soil just on the verge of drying out, yet never allowing it to do so, is the whole secret of starting Heliotrope from seeds. It is best to sow the seed in moist soil to avoid the necessity of watering afterward, as is done with other seeds; if the soil is just wet enough to be crumbly, neither wet nor sticky, and can be kept so, they will prosper. Cover the seed lightly with white sand and remove the glass if any appreciable moisture appears—anything more than a fine mist. It germinates in from fifteen to twenty days, and the plants require no special care beyond good soil, warmth, and plenty of sunshine with frequent waterings. When grown as house-plants they should be showered once or twice a day to prevent the inroads of the red spider—their worst enemy.
There is no more desirable bedding plant than the Heliotrope, and the more freely it is cut by removing generous portions of stem with the blossom the more freely it will bloom. It is admirable for replacing Pansies and may be grown on in the hotbed until the Pansy’s day is past. Where there is not enough Heliotrope for large bedding operations, purple Ageratum may be combined with the Heliotrope with excellent effect; this is a method often employed in the city parks, and when judiciously done one scarcely notices that the beds are not all Heliotrope. Plants may be taken up in the fall and cut back for winter blooming. Blossoms always form on the terminals of the branches.