Substrates for those who grow vegetable seedlings
Formulas for horticulture, seedling production and propagation nurseries. Fine granulometry, high content of blonde peat from Baltic and German sources, buffered capacity calibrated for the first 21–30 days to support germination and root development.
What is a substrate for vegetable seedlings
A substrate for vegetable seedlings is a fine granulometry formula (predominantly 0–5 mm fraction), with a high content of blonde peat from Baltic sources and lightweight structural materials, calibrated to support germination and root development during the first 3–4 weeks of cultivation. The buffer capacity is set for optimal results with the majority of solanaceous, cucurbit and brassica crops in direct seeding.
Four technical criteria for professional seedling production
The parameters that distinguish a seedling formula from a repotting or outdoor formula.
Fine granulometry 0–5 mm
A predominantly fine fraction ensures uniform seed coverage and consistent seed-to-substrate contact. Coarse fraction should be minimised: it risks leaving air pockets around the seed and delaying germination.
High Baltic blonde peat content
A high proportion of block-cut blonde peat from Baltic sources provides water retention and buffer capacity. DX formulas incorporate a small share of brown peat and fiber to regulate water-holding capacity during the germination cycle.
Stable pH 5.5–6.0
Buffer capacity calibrated to maintain pH within the optimal range for solanaceous seeds (tomato, pepper, aubergine) and cucurbits. Dolomite and process correctors at controlled doses, not added at the production site.
Microbiological sterility
Raw materials selected from regulated extraction sites in Lithuania and Germany, with low native microbial load. The risk of damping-off is reduced through selected supply chain sourcing, not through post-formulation chemical treatments.
Arber substrates for vegetable seedlings
Formulas for horticulture, seedling production and propagation nurseries. Fine granulometry and calibrated buffer capacity to support germination and root development.
DX Seeding
DX Summer
DX-60 W 0-10 + Perlite
DX-OX
Press RK-W
Press Top
Tray SSF3
Unipot Seeding 70/30
Bio Seeding
Comparative table — Vegetable seedlings
| SKU | Structure | pH | EC mS/cm | Recommended pot |
|---|---|---|---|---|
| DX Seeding | Fine | 5.5-6.5 | 0.6-1 mS/cm | n/d |
| DX Summer | Fine | 5.5-6.5 | 0.6-1.0 mS/cm | n/d |
| DX-60 W 0-10 + Perlite | Medium-fine | 5.5-6.5 | 0.7-1.3 mS/cm | n/d |
| DX-OX | Fine | 5.5-6.5 | 0.4-0.8 mS/cm | n/d |
| Press RK-W | Fine | 5.5-6.5 | 0.4-0.7 mS/cm | n/d |
| Press Top | Extra fine | 5.2-6 | 0.6-1 mS/cm | n/d |
| Tray SSF3 | Fine | 5.2-6 | 0.6-1 mS/cm | n/d |
| Unipot Seeding 70/30 | Fine | 5-6 | 0.7-1.3 mS/cm | n/d |
| Bio Seeding | Fine | 5.4-6.2 | 0.6-1 mS/cm | n/d |
Indicative sample data, referenced to the formulation batch. Declared tolerances are given in the technical data sheet for each individual SKU.
What professional seedling growers ask
Can I get a custom formula to specification?
Yes. For volumes compatible with a Pro seedling operation’s production cycle, we develop custom formulas based on crop, irrigation system and location. The process starts with a technical request to your regional agent, who brings the constraint parameters to the production team. The first pilot batch typically arrives within 3–4 weeks.
How long does delivery take across Italy?
We deliver across Italy, with logistics organized to keep lead times short. Transport is included in the price to the gate, with no full-truck requirement. Typical lead times are 3–7 working days depending on region and format.
Do you hold supply chain certifications?
Yes. The German section of the supply chain is certified HORTICERT, the scheme that verifies ecological, social and economic sustainability. Selected professional raw materials are certified under the RAL procedure of the Gütegemeinschaft Substrate für Pflanzen. The organic lines use raw materials included on the FiBL list.
How does a quote or sample request work?
The “Request a quote” form collects your crop, estimated annual volumes and region. The request goes directly to your regional agent, who prepares the sample and technical data sheet and contacts you directly.
How does agronomic support work?
Your regional agent is the primary technical point of contact: formula selection, pilot trial in the greenhouse, analysis of any mid-cycle issue. For complex cases, the agent involves the in-house formulation team. Substrate and technical support are part of the same package — they are not separate services.
Do I need to change formula between summer and winter cycles?
It depends on your setup. In a heated greenhouse with automatic irrigation, DX Seeding covers the full year. In cold greenhouses or tunnels with high-temperature summer cycles, DX Summer is the higher water-retention variant that reduces drying stress. Your regional agent will suggest the right combination based on your declared cycle.
Do you also produce potted or field-grown plants? Go to /produzioni/piante-in-vaso/ or to /produzioni/piante-da-esterno/.
Want to test an Arber substrate in your seedling operation?
Request a quote, talk to the agronomist about your crop, or find your local distributor. Every request goes to your regional agent, who will contact you directly.