Leucospermum heterophyllum can be propagated from semi-hardwood cuttings taken in autumn or spring. Collect cuttings early in the morning to reduce moisture loss and mist them lightly with water when collecting. Cuttings are treated with a rooting hormone for about 5 seconds to stimulate root formation. Insert the cuttings in a well-drained, aerated medium consisting of either 70% perlite and 30% fine bark, or a mixture of coarse sand and finely milled pine bark. The cuttings should be placed on tray with sufficient space to allow for air circulation. Place trays on heated benches at ±25 °C under intermittent misting.

Cuttings should be treated regularly with fungicide to prevent fungal infections. Remove any dead leaves or wilting cuttings during the rooting process. Once rooted, move the cuttings to a hardening-off house for about two weeks, then pot them into small nursery bags filled with a well-drained, acidic growing medium.

Seeds can be collected one to two months after flowering, when florets begin turning brown. Harvest seed heads, dry them, and clean to extract the seeds. Since the seeds are hard and covered by an elaiosome, soak them in a 1% hydrogen peroxide solution for 24 hours to soften the seed coat. Rub the seeds gently in a bag or by hand to remove the elaiosome. Discard any soft or squashed seeds, as these are immature.

Treat seeds with fungicide before sowing, and continue weekly applications to prevent fungal infections, as seedlings are highly susceptible. Sow seeds in autumn, between March and May, in a well-aerated medium, applying smoke treatment with dry and green fynbos material to stimulate germination. Seedlings are ready for potting-up once they have produced their first true leaves, which helps reduce wilting and improves survival rates. Both seedlings and rooted cuttings should be kept under a shade net that reduces direct sunlight, prevents scorching, and helps retain soil moisture in nursery bags. Once the plants have developed strong roots, they may gradually be moved into full sun and planted out after two to three years.

When planting in the garden, keep the soil moist by applying a 5 mm layer of mulch. This helps cool the roots, conserve soil moisture, and suppress weed growth.