HARZFEUER F1 - Hybrid Round Tomato Seeds

Tomatoes need a long growing season and cannot tolerate frost. Give them a head start by sowing indoors from early spring to plant into a greenhouse in late spring, or to plant outside in early summer. Don't sow too early as plants will fast outgrow space on a windowsill. 

Fill a cell tray with seed-starting mix and sow a single seed I in (2 cm) deep into each module. Cover with potting mix, label, and water well. Enclose the tray in a clear plastic bag or place into a propagator; position on a sunny windowsill to provide extra warmth. Once the seedlings have germinated remove the covers and water to keep moist. Pot each plant into a 3½ in (9 cm) pot when it reaches about 3 in (8cm) in height and has three true leaves. Space out the plants so they do not touch. 

PLANT OUT: Acclimatize plants raised under cover to outdoor conditions by moving them outside for progressively longer each day over two weeks in late spring. Plant out in early summer, once the risk of frost has passed, or into an unheated greenhouse in late spring. Vining tomatoes thrive in full sun when planted into fertile soil, grow bags, or containers at least 9 in (23 cm) in diameter. Space them about 18 in (45 cm) apart and plant them deeply with their lowest leaves just below soil level. Add strong supports, such as canes or metal spirals, at least 5 ft (1.5 m) tall for each plant and tie in the stem loosely with garden twine. 

TRAIN UP SUPPORTS: Keep the main stem of each plant tied to its support as it grows. Pinch out side-shoots, which form between each leaf and the main stem, to stop bushy growth and encourage flowering. Pinch out the growing point at the tip of each plant in late summer to early fall when the end of the growing season is near, to divert resources to ripening. 

WATER AND FEED: Outdoor tomatoes need watering only in very dry weather before flowering, and soaking weekly if conditions remain dry after that. In fertile soil they need little feeding but benefit from a weekly feed with a liquid tomato fertilizer as fruit trusses form. Plants grown in containers or under cover need watering once or even twice a day in summer to maintain healthy growth. Once the first truss of fruit sets, feed with liquid tomato fertilizer twice a week. 

Pick fruits as soon as they ripen by snapping their short stems where they join the vine. Tomatoes are spoiled by cold conditions, so make sure to harvest outdoor crops before the first frost and never store picked tomatoes in the fridge. Unripe fruit can be cut from the plant on the vine and brought indoors to ripen. Green tomatoes can also be made into chutney.