March planting of tomatoes in the greenhouse

Soil and temperature preparation

Before planting tomatoes in a greenhouse in March, the soil temperature must be at least 12°C 15 cm below the surface. Insert the thermometer in the morning. If it's colder, the plant won't grow, it will just "wait".

Important preparatory activities:

• Dig deep 25-30 cm
• Add 5-7 cm of mature compost
• Add calcium if necessary (tomatoes are big consumers)
• Cover the soil with black foil 2 weeks in advance to warm it up

Greenhouse variety selection

For March planting, choose varieties with a shorter vegetation period (60-70 days). Suggestions:

• Sungold F1, golden-orange cherry, the sweetest
• Stupice, Czech variety, fast and resistant
• Black Cherry, dark red cherry, decorative
• Roma VF, tomato for canning
• Bull's Heart, large heart-shaped, sweet

Seedling cultivation

Cultivate seedlings at home from the end of January:

1. Sowing in 5 cm pots: 25-30 Jan
2. First transplanting into larger 10 cm pots: 25 Feb (after 30 days)
3. Hardening: place outside for 7-10 days (12-15°C)
4. Transplanting into the greenhouse: 15 Mar (after 50 days from sowing)

The seedling is ready when it has 6-8 leaves and is 20-25 cm tall.

Transplanting into the bed

Spacing: 50 cm between plants, 80 cm between rows. Planting:

1. Dig a 25 cm deep hole
2. Add a spoonful of slow-release NPK fertilizer
3. Plant the seedling 5 cm deeper than it was in the pot (encourages additional roots)
4. Support the seedling with a bamboo stick or metal mesh
5. Water with lukewarm water

Care in the first weeks

After planting:

• First 2 weeks: water daily (seedling develops roots)
• Then 2-3 times a week: 2-3 L of water per plant
• Water at the roots, not on the leaves (powdery mildew)
• Remove side shoots (suckers) as soon as they appear

"March tomatoes are not for everyone, but those who succeed have the sweetest, as they ripen in the cooler spring, not in the heat.", Slovenian tomato growers