I'd recommend considering not using seeds for propagating these specific lavender varieties. Here's why: Lavender varieties like "Little Lottie," "Hidcote Pink," and others are often cultivated for specific characteristics, such as flower color, plant size, and growth habit. These traits are maintained through vegetative propagation methods like cuttings or tissue culture. Seeds, even if they are from a specific cultivar, can result in plants that vary significantly from the parent due to genetic recombination. This means your seed-grown plants may not exhibit the traits you expect from the named cultivar.
For a more consistent result, it's better to purchase plants or cuttings from nurseries. This way, you're more likely to get the true characteristics of the cultivar you're interested in. If you do want to experiment with seeds, you should be prepared for some variability in the plants that you grow.